-
Am J Clin Pathol 2011;135:291-303 291291 DOI:
10.1309/AJCPVFY95MAOBKRS 291
American Society for Clinical Pathology
Hematopathology / PseudoPelger-Hut Anomaly Induced by
Medications
CME/SA
M
PseudoPelger-Hut Anomaly Induced by Medications
A Clinicopathologic Study in Comparison With Myelodysplastic
SyndromeRelated PseudoPelger-Hut Anomaly
Endi Wang, MD, PhD,1 Elizabeth Boswell, MD,1 Imran Siddiqi, MD,
PhD,2 Chuanyi Mark Lu, MD,3 Siby Sebastian, PhD,1 Catherine Rehder,
PhD,1 and Qin Huang, MD, PhD4
Key Words: PseudoPelger-Hut anomaly; Medications; Iatrogenic;
Myelodysplastic syndrome; Neutrophilic dysplasia
DOI: 10.1309/AJCPVFY95MAOBKRS
A b s t r a c t
PseudoPelger-Hut anomaly (PPHA) has been documented in
association with transplant medications and other drugs. This
iatrogenic neutrophilic dysplasia is reversible with cessation or
adjustment of medications but is frequently confused with
myelodysplastic syndrome (MDS) based on the conventional concept
that PPHA is a marker for dysplasia. We investigated the
clinicopathologic features in iatrogenic PPHA and compared them
with MDS-related PPHA. The 13 cases studied included 5 bone
marrow/stem cell transplantations, 3 solid organ transplantations,
1 autoimmune disease, 3 chronic lymphocytic leukemias, and 1 breast
carcinoma. For 12 cases, there was follow-up evaluation, and all
demonstrated at least transient normalization of neutrophilic
segmentation. All 9 cases of MDS demonstrated at least 2 of the
following pathologic abnormalities on bone marrow biopsy:
hypercellularity (8/9), morphologic dysplasia (8/9), clonal
cytogenetic abnormality (7/9), and increased blasts (3/9), whereas
these abnormalities were typically absent in iatrogenic PPHA.
Iatrogenic PPHA displayed a higher proportion of circulating PPHA
cells than in MDS (mean, 47.4%; SD, 31.6% vs mean, 12.3%; SD, 9.8;
P < .01). A diagnostic algorithm is proposed in which isolated
PPHA is indicative of transient or benign PPHA unless proven
otherwise.
Pelger-Hut anomaly (PHA) was first described by Karl Pelger in
19281 and was further defined as a benign trait with autosomal
dominant inheritance by G.J. Hut in 1931.2 This hereditary anomaly
is characterized by round, oval, peanut-shaped, coffee beanshaped,
or symmetric bilobed nuclei with abnormally clumped chromatin in
granulocytes. Despite these morphologic abnormalities, granulocyte
function, including neutrophilic chemotaxis, phagocytosis, and
cytolytic activity, remains normal, and people with hereditary PHA
do not have increased susceptibility to bacterial infections.3 In
contrast, pseudoPelger-Hut anomaly (PPHA) is an acquired alteration
of neutrophils closely resembling hereditary PHA in morpho-logic
features. While its presence in some myeloid neoplasms, such as
myelodysplastic syndrome (MDS), is well-established and has
important diagnostic implications,4-6 PPHA can also be induced by a
variety of nonneoplastic etiologies as a transient or reversible
phenomenon.7-20 Among the multiple other causes, increased use of
transplant medications7-10 and other drugs11-17 has become a major
etiology for this morphologic deviation.
Because of the conventional concept that PPHA is a morphologic
marker for myelodysplasia,4-6 the presence of iatrogenically
induced PPHA in the peripheral blood and/or bone marrow may cause
diagnostic confusion, particularly in patients with a history of
treatment for malignant neoplasms and subsequent chronic
cytopenias. As the diagnostic impli-cations of iatrogenic PPHA vs
MDS-associated PPHA are markedly divergent, accurate distinction of
these processes is important. We compared peripheral blood and bone
marrow findings in iatrogenic PPHA with MDS-associated PPHA to
characterize and define features that can aid in distinguishing
these entities.
Upon completion of this activity you will be able to: define the
characteristics of iatrogenic pseudoPelger-Hut anomaly
(PPHA). distinguish iatrogenic PPHA from myeloid
neoplasmassociated PPHA
based on differences in associated clinicopathologic features.
list the common medications that have been reported to induce
PPHA.
The ASCP is accredited by the Accreditation Council for
Continuing Medical Education to provide continuing medical
education for physicians. The ASCP designates this educational
activity for a maximum of 1 AMA PRA Category 1 Credit per article.
This activity qualifies as an American Board of Pathology
Maintenance of Certification Part II Self-Assessment Module.
The authors of this article and the planning committee members
and staff have no relevant financial relationships with commercial
interests to disclose.
Questions appear on p 312. Exam is located at
www.ascp.org/ajcpcme.
-
292 Am J Clin Pathol 2011;135:291-303292 DOI:
10.1309/AJCPVFY95MAOBKRS
American Society for Clinical Pathology
Wang et al / PseudoPelger-Hut Anomaly Induced by Medications
Materials and Methods
Case Selection
For the study, 13 cases of iatrogenic PPHA and 9 cases of MDS
with PPHA were identified from our bone marrow biopsy databases
using the search phrase Pelger-Hut anomaly. These included 14 cases
(7 iatrogenic PPHAs and 7 MDS with PPHA) from Duke University
Medical Center, Durham, NC; 3 cases (iatrogenic PPHAs) from
University of California at San Francisco; 2 cases (MDSs with PPHA)
from San Francisco Veteran Affairs Medical Center, San Francisco,
CA: 2 cases (iatrogenic PPHAs) from City of Hope National Medical
Center, Duarte, CA; and 1 case (iatrogenic PPHA) from USC Medical
Center, Los Angeles, CA. The diagnoses of iatrogenic PPHA were
confirmed by clinical history, laboratory tests, and/or,
ultimately, by resumption of normal segmentation in neutrophils or
a significant change in proportion of PPHA cells occurring
spontaneously or in correlation with dose adjustment of relevant
medications (see later text). The diagnoses in 9 cases of MDS with
PPHA were confirmed according to the 2008 World Health Organization
clas-sification.21
Cytomorphologic and Histologic EvaluationPeripheral blood smears
were stained with Wright
stain, bone marrow aspirate smears and biopsy touch imprints
were stained with Wright-Giemsa, and bone marrow core biopsies and
clot sections were stained with H&E. The cases were reviewed
independently by 4 hematopathologists (E.W., I.S., C.M.L., and
Q.H.). PPHA neutrophils were identified by their unilobed or
symmetric bilobed nuclei, abnormally clumped chromatin, and
rela-tively abundant cytoplasm with pink or yellowish granules. We
examined 200 neutrophils in peripheral blood smears, and
proportions of PPHA cells were calculated as percent-age of total
neutrophils. In addition, other morphologic dysplasia, bone marrow
cellularity, and blast counts were also evaluated. The presence of
other dysplastic changes in erythroid, granulocytic, and
megakaryocytic lineages was determined according to the description
in the 2008 World Health Organization Classification.21 Bone marrow
cellularity was defined as hypercellular when it was higher than 1
SD above the age-adjusted mean, as hypocellular when lower than 1
SD, and as normocellular when within 1 SD.22
Conventional Cytogenetic StudiesCytogenetic analysis was
performed on 2 to 4 mL
of bone marrow aspirate from each case. Two cultures were
initiated from each fresh, anticoagulated specimen in
complete tissue culture medium. Cells were incubated for 24 and
48 hours without mitogen stimulation, except for the 2 CLL samples,
in which both B cellstimulated and B cellunstimulated cultures were
initiated and examined. Chromosome preparations including
harvesting and GTW-banding were made using standard methods.
Cytogenetic abnormalities were classified according to the
International System for Human Cytogenetic Nomenclature.
Bone Marrow Engraftment AnalysisHighly purified DNA was
extracted from the pretrans-
plantation, donor, and posttransplantation samples fol-lowing
routine laboratory methods. For positive selection of lymphocytes
or granulocytes from posttransplantation samples, magnetically
labeled antihuman CD3 or CD15 antibodies (isotype, mouse IgG1 and
IgM , respectively) and the RoboSep automated cell separator
(StemCell Technologies, Vancouver, Canada) were used. The
extract-ed sample genomic DNA was subjected to multiplexed
polymerase chain reaction (PCR)-mediated amplification reaction
targeting a total of 15 autosomal short tandem repeat (STRs)
markers and 1 STR marker on the pseudo-autosomal region of the X
and Y chromosomes (PowerPlex 16 System, Promega, Madison, WI).
Following PCR amplification, the fluorescently labeled PCR products
were resolved by capillary electrophoresis on the ABI 3130xl
Genetic Analyzer and analyzed by GeneMapper software (Applied
Biosystems, Foster City, CA) to resolve the num-ber of repeats and
relative abundance of each repeat for each STR locus. These data
were then used to calculate the percentage of donor and/or
recipient cells in the posttrans-plantation sample using the donor
and pretransplantation recipient STR profiles.
Assessment of Resolution of PPHA CellsTo assess for resolution
of PPHA neutrophils or nor-
malization of neutrophilic segmentation, manual differen-tials
of WBC on peripheral blood smears were evaluated following the
index bone marrow biopsy for each case. Resolution of PPHA cells
was defined by the absence of PPHA cells on follow-up peripheral
blood smears per-formed after the bone marrow biopsy. In cases in
which PPHA cells were absent in multiple peripheral blood samples,
the earlier time of resolution was recorded as the time of
resolution.
Statistical AnalysisThe statistical analyses were performed with
SAS ver-
sion 9 (SAS Institute, Cary, NC). The Student t test and
Wilcoxon-Mann-Whitney test were used to test the statisti-cal
significance of differences in circulating PPHA cells between the
groups.
-
Am J Clin Pathol 2011;135:291-303 293293 DOI:
10.1309/AJCPVFY95MAOBKRS 293
American Society for Clinical Pathology
Hematopathology / Original Article
Results
Clinical Information
Of the 13 cases of iatrogenic PPHA, 5 were seen fol-lowing
allogeneic bone marrow or stem cell transplanta-tion for acute
myeloid leukemia (AML), including 2 de novo AMLs and 3 AMLs arising
from preexisting MDS. Three cases occurred in the setting of
chronic lymphocytic leukemia (CLL), 2 in liver transplant
recipients (history of hepatocellular carcinoma and autoimmune
hepatitis, respectively), 1 in a heart transplant recipient
(history of cardiomyopathy), 1 in a case of autologous stem cell
transplantation with treatment for breast carcinoma, and 1 in
autoimmune disease treated with mycophenolate mofetil. Among these
13 cases, 9 were men and 4 were women. Ages ranged from 20 to 75
years, with a median of 57 years Table 1. The 9 MDS cases with PPHA
com-ponents included refractory anemia with excess blasts (3
cases), refractory anemia (2 cases), therapy-related MDS (2 cases),
refractory cytopenia with multilineage dysplasia (1 case), and
refractory anemia with ringed sideroblasts (1 case). Among the MDS
cases, 6 were men and 3 were women. Ages ranged from 53 to 82 years
with a median of 67 years Table 2. Similar to the MDS cases, all
patients with iatrogenic PPHA had anemia, neutropenia, and/or
thrombocytopenia at the time of bone marrow biopsy, with the
exception of 1 case (case 13; Table 1). In the iatrogenic PPHA
cases, bone marrow biopsies were performed to rule out relapsed
acute myeloid leukemia or high-risk MDS in 5 cases following bone
marrow transplantation (cases 1-5), to rule out therapy-related
myeloid neoplasms in 4 cases (cases 6-9), to assess disease status
of CLL in 3 cases (cases 10-12), and to rule out
myelodysplastic/myeloprolif-erative neoplasm in 1 case (case
13).
Cytomorphologic and Histologic EvaluationCirculating PPHA cells
in the iatrogenic group typi-
cally displayed hypolobated nuclei with clumped chroma-tin Image
1A, Image 1B, Image 1C, Image 1D, Image 1E, Image 2A, Image 2B,
Image 2C, and Image 2D. The majority of the cells had nuclear
contours that were round (Images 1A and 2A) or oval (Images 1B and
2B), but coffee beanshaped (Images 1C and 2C), peanut-shaped
(Images 1D and 2D), bilobed (Image 1E), and occasional other forms
were also noted. Some PPHA cells also con-tained detached round
nuclear fragments in the cytoplasm, so called Howell-Jollylike
inclusions (data not shown). Eosinophils were unaffected, retaining
their lobated mor-phologic features Image 1F. The median proportion
of circulating PPHA cells was 33% of neutrophils (range, 11%-94%;
mean, 47.4%; SD, 31.6%) in the iatrogenic
PPHA group, while in the MDS group, it was 9% (range, 2%-28%;
mean, 12.3%; SD, 9.8%). The difference was statistically
significant between the 2 groups (P < .01). In addition, PPHA
cell nuclei in the iatrogenic group were more uniformly unilobed
and contained homogeneously clumped chromatin; in comparison, those
in the MDS group contained irregularly hypolobated nuclei, although
their nuclear chromatin was clumped in a similar manner in some
cases Image 3A and Image 3B. On bone marrow examination, 11 of 13
iatrogenic cases displayed normal or decreased bone marrow
cellularity; the remaining 2 were CLL cases that showed increased
bone marrow cellular-ity due to infiltration by CLL-type leukemic
cells Image 2F. Although PPHA cells or their immediate precursors
were noted Image 1G and Image 2E, no significant morphologic
dysplasia other than PPHA was appreciable, and blasts were not
increased in the iatrogenic group. In contrast, among the 9 MDS
cases, 8 (89%) showed mild to marked dysplasia other than PPHA
Image 3C, Image 3D, and Image 3E, 3 (33%) had increased blasts
(Image 3E), and 8 (89%) demonstrated significantly increased bone
marrow cellularity Image 3F.
Cytogenetic StudiesCytogenetic analyses were performed on bone
mar-
row specimens from 10 iatrogenic PPHA cases. Of these, 9 showed
a normal karyotype, while 1 CLL case demon-strated a complex
cytogenetic abnormality in a mitogen-stimulated culture, consistent
with a B-cell clone from the underlying CLL. All 9 cases of MDS had
conventional cytogenetic analysis performed, and 7 of 9 showed
clonal cytogenetic abnormalities Image 4 (case 7; Table 2), while
the remaining 2 cases had a normal karyotype.
Bone Marrow Engraftment AnalysisAmong the iatrogenic PPHA cases,
3 of 5 bone mar-
row or stem cell transplant recipients had concurrent
engraftment studies performed, with 2 showing donor cell
engraftment, confirming the donor origin of PPHA cells Figure 1
(case 1; Table 1), and 1 demonstrating recipient origin, the latter
representing an engraftment failure. Donor origin of bone marrow
hematopoietic elements was also seen in 2 of 4 bone marrow or stem
cell transplant cases by cytogenetic studies (as determined by
discordance of sex chromosome in cases 2 and 5; Table 1).
Clinical Follow-up and Resolution of PPHA in Peripheral
Blood
All but 1 case of iatrogenic PPHA had follow-up evaluation of
peripheral blood smears. All cases evaluated showed evidence of
normalized neutrophilic segmenta-tion based on manual WBC
differential or examination
-
294 Am J Clin Pathol 2011;135:291-303294 DOI:
10.1309/AJCPVFY95MAOBKRS
American Society for Clinical Pathology
Wang et al / PseudoPelger-Hut Anomaly Induced by Medications
of follow-up peripheral blood smears, including the case with
bone marrow engraftment failure (case 3; Table 1). In 1 patient
(case 8; Table 1), the decrease in PPHA cells was transient,
decreasing from 64% at the time of bone marrow biopsy to 8% 13
weeks later, with subsequent return of high numbers of PPHA cells.
The return of PPHA neutrophils in this patient was noted during an
episode of acute renal failure (slow increase in PPHA cells with
rising serum creatinine level). In the remaining iatrogenic PPHA
cases evaluated, neutrophilic segmentation completely normalized
Image 1H. The time to resolution ranged from 3 to 29 weeks after
the index bone marrow biopsy with a median of 8.5 weeks.
Discussion
PPHA is an acquired alteration of neutrophils with morphologic
features resembling hereditary PHA. As in the hereditary form, PPHA
is characterized by neutrophils with abnormally condensed chromatin
and hypolobated nuclei, which can be round, oval, peanut-shaped,
coffee beanshaped, or symmetrically bilobed. PPHA can be seen in 2
major categories of acquired granulocytic changes.
First, it can occur in myeloid neoplasms such as MDS. In these
cases, PPHA is considered a component of the malignancy,4-6 and the
change persists or progresses with-out treatment of the underlying
myeloid neoplasm. The second category of PPHA occurs in association
with various infections18-20 or can be induced by certain
medications.7-17 The changes in the latter category are reversible
following recovery from the underlying conditions or after
adjust-ment or discontinuation of culpable medications. Because of
the conventional acceptance that PPHA is a marker for
myelodysplasia,4-6 the presence of iatrogenic PPHA in the
peripheral blood or bone marrow, particularly in patients with
anemia, neutropenia, and/or thrombocytopenia, often causes
confusion because it suggests MDS or a related myeloid neoplasm.
This diagnostic confusion becomes even more critical in patients
after bone marrow or hematopoi-etic stem cell transplantation for
MDS or AML because the presence of PPHA may suggest relapsed
disease or a therapy-related myeloid neoplasm.
In this case series, all patients with medication-related
(iatrogenic) PPHA underwent bone marrow biopsies owing to anemia,
neutropenia and/or thrombocytopenia, or pancy-topenia. In all of
these cases, except for the 3 CLL cases, MDS or a related myeloid
neoplasm was initially considered
Table 1Evaluation of PPH Anomaly Associated With
Medications*
CBC
Case No./ WBC Count Neutrophils Hemoglobin Platelets Blasts PPH
Cells Sex/Age (y) History Transplant Medications ( 109/L) ( 109/L)
(g/L) ( 109/L) (%) (%)
1/M/67 AML/MDS Allo BM MMF; tacrolimus; acyclovir; 1.4 0.74 129
112 0 94 posaconazole; others2/M/20 MDS Allo BM MMF; tacrolimus;
ganciclovir; co- 3.5 1.8 102 31 0 21 trimoxazole; itraconazole;
others3/M/52 AML/MDS Allo BM MMF; tacrolimus; G-CSF; others 2.0
0.81 108 22 0 33 4/M/68 AML Allo BM MMF; tacrolimus; others 4.6
3.13 111 62 0 29 5/F/50 AML Allo BM MMF; tacrolimus; others 10.6
9.33 91 105 0 17 6/F/68 AI MMF; prednisone; others 0.5 0.25 112 0.9
0 11 7/M/56 HCC Liver MMF; tacrolimus; others 3.5 2.37 89 170 0 90
8/M/24 Cirrhosis Liver MMF; tacrolimus; ganciclovir; others 1.4
0.77 93 93 0 64 9/M/57 Cardiomyopathy Heart MMF; tacrolimus; others
3.3 1.2 92 320 0 19 10/M/71 CLL Co-trimoxazole; ciprofloxacin; 2.3
0.92 118 93 0 85 bendamustine; acyclovir; others11/M/75 CLL
Fludarabine; rituximab; others 13.9 4.17 104 87 0 57 12/M/72 CLL
Fludarabine; rituximab; others 0.9 ND 131 119 0 79 13/F/41
Metastatic Auto BM GCSF; letrozole; citalopram; 22.2 20.2 119 257 0
17 breast cancer lorazepam; others
AI, autoimmune disease; allo BM, allogeneic BM/hematopoietic
stem cell; AML, acute myeloid leukemia; Auto, autologous
hematopoietic stem cell; BM, bone marrow; CLL, chronic lymphocytic
leukemia; GCSF, granulocyte colony-stimulating factor; GM-CSF,
granulocyte-macrophage colony-stimulating factor; HCC,
hepatocellular carcinoma; Hyper, hypercellular; Hypo, hypocellular;
MDS, myelodysplastic syndrome; MMF, mycophenolate mofetil; NA, not
applicable; ND, not done; Norm, normocellular; PPH,
pseudoPelger-Hut (neutrophils).
* Values for WBCs, neutrophils, hemoglobin, and platelets are
given in Systme International units; conversions to conventional
units are as follows: WBCs and neutrophils (/L), divide by 0.001;
hemoglobin (g/dL), divide by 10.0; and platelets ( 103/L), divide
by 1.0.
Morphologic dysplasia other than PPH anomaly. In case 8, PPH
anomaly cells decreased transiently at 13 weeks, then recurred at
high levels during an episode of renal failure. In case 11, PPH
anomaly cells persisted in the peripheral blood smear 1 week after
the index BM biopsy, and the patient was then lost to
follow-up.
-
Am J Clin Pathol 2011;135:291-303 295295 DOI:
10.1309/AJCPVFY95MAOBKRS 295
American Society for Clinical Pathology
Hematopathology / Original Article
in the differential diagnosis for the cytopenias. Furthermore, a
diagnosis of MDS or related myeloid neoplasm was made or suggested
in the diagnostic comment when PPHA was identified in peripheral
blood and bone marrow aspirate smears. A typical diagnostic error
is exemplified by case 7 in the series (Table 1). Briefly, this
56-year-old man devel-oped chronic anemia 2 years after liver
transplantation for hepatocellular carcinoma. Routine peripheral
blood smear review revealed numerous PPHA cells, which were also
noted in the subsequent bone marrow biopsy. Considering the
concomitant peripheral monocytosis and clinical his-tory, a
diagnosis of chronic myelomonocytic leukemia, probably
therapy-related was suggested in the pathology report, even though
neither additional dysplastic changes nor increased blasts were
identified and conventional cytogenetic analysis showed a normal
male karyotype. Fortunately, the treatment was held owing to other
medical issues. A follow-up peripheral blood smear demonstrated
BA
CImage 1 (Case 1, Table 1) Reversible pseudoPelger-Hut anomaly
(PPHA) in a hematopoietic stem cell transplant recipient. Note the
hypolobated neutrophils with abnormally clumped chromatin and round
(A), oval (B), and coffee beanlike (C).
BM
Blasts Cyto- Resolution/ TimeCellularity (%) Dysplasia genetics
Engraftment to Resolution (wk)
Hypo
-
296 Am J Clin Pathol 2011;135:291-303296 DOI:
10.1309/AJCPVFY95MAOBKRS
American Society for Clinical Pathology
Wang et al / PseudoPelger-Hut Anomaly Induced by Medications
Image 1 (cont) Peanut-like (D), and bilobed (E) nuclear contours
in peripheral blood; an eosinophil with normal segmentation in
peripheral blood (F); PPHA cell precursors (G, right field); and a
few normal-appearing erythroid normoblasts (G, left field) on the
bone marrow touch imprint and eventually normalized neutrophilic
segmentations in peripheral blood (H) (A-F and H, Wright, 1,000; G,
Wright-Giemsa, 1,000).
D E
F G
H
-
Am J Clin Pathol 2011;135:291-303 297297 DOI:
10.1309/AJCPVFY95MAOBKRS 297
American Society for Clinical Pathology
Hematopathology / Original Article
A B
C D
E F
Image 2 (Case 10, Table 1) Reversible pseudoPelger-Hut anomaly
(PPHA) in a patient with chronic lymphocytic leukemia (CLL). Note
the hypolobated neutrophils with abnormally clumped chromatin and
unilobed nuclear contours in peripheral blood (A, B, C, and D,
round, oval, coffee beanlike, and peanut-like nuclear shapes,
respectively); 1 unilobed neutrophil or PPHA cell precursor near
the center of the image in a background of CLL cells on marrow
aspirate smear (E); and CLL cell infiltrate (lower field) in bone
marrow on bone marrow biopsy section (F) (A-D, Wright, 1,000; E,
Wright-Giemsa, 1,000; F, H&E, 200).
-
298 Am J Clin Pathol 2011;135:291-303298 DOI:
10.1309/AJCPVFY95MAOBKRS
American Society for Clinical Pathology
Wang et al / PseudoPelger-Hut Anomaly Induced by Medications
A B
C D
E F
Image 3 (Case 1, Table 2) PseudoPelger-Hut anomaly (PPHA) and
associated other pathologic abnormalities in a patient with
myelodysplastic syndrome (MDS). A and B, Note the hypolobated
neutrophils with abnormally clumped chromatin and twisted or
irregular nuclear contours in peripheral blood (A and B, Wright,
1,000). C, D, and E, Many PPHA cells in the marrow aspirate smear
(C-E), markedly dysplastic erythroid normoblasts (C-E, arrows), 1
dysplastic megakaryocyte (micromegakaryocyte) (D, arrowhead), and
increased blasts (E, arrowheads) in aspirate smear (C-E,
Wright-Giemsa, 1,000). F, Hypercellular bone marrow with increased
immature cells on bone marrow biopsy section (H&E, 200).
-
Am J Clin Pathol 2011;135:291-303 299299 DOI:
10.1309/AJCPVFY95MAOBKRS 299
American Society for Clinical Pathology
Hematopathology / Original Article
should be used with caution when distinguishing between
iatrogenic PPHA and MDS.
Of interest, the MDS cases in this study displayed high-grade
features with increased blasts (3/9) or a high frequency of clonal
cytogenetic abnormalities (7/9). In particular, all 6
normalized neutrophilic segmentation a few months later, and,
thus, the diagnosis was corrected to reversible PPHA, probably
related to transplant medications. Clearly, rec-ognition of the
benign nature of iatrogenic PPHA in these cases is crucial to avoid
unnecessary diagnostic intervention and medical treatment.
Clinicopathologic studies comparing the peripheral blood and
bone marrow findings in benign vs neoplastic PPHA are lacking in
the literature. We investigated the features of 13 cases of
iatrogenic PPHA and compared them with 9 cases of MDS-related PPHA.
In contrast with MDS, we found that iatrogenic PPHA tends to have a
higher proportion of circulating PPHA neutrophils (median, 33% vs
9%; mean, 47.4% vs 12.3%; P < .01), which show more homogeneous
unilobed nuclei. The proportion of PPHA cells in the iatrogenic
group is within the ranges previ-ously reported in the
literature,7,8,11 while that for the MDS group seems to be higher
than what has been described in the literature,6,23 likely owing to
a selection bias in this subset of MDS. However, the quantitative
differences in PPHA cells between the iatrogenic and MDS groups is
not as obvious in the bone marrow aspirate smear as in peripheral
blood, which may be explained by intramedul-lary destruction
(apoptosis) of neoplastic myeloid elements in MDS.23-25 As the
timing of peripheral blood and bone marrow analyses can be quite
variable in iatrogenic PPHA cases, a subset of these cases might be
evaluated at periods beyond the peak of PPHA cell formation, eg,
due to waning drug effects, and, thus, the proportion of
circulating PPHA cells could be relatively low, as was seen in
cases 2, 5, 6, and 13 of the iatrogenic group (Table 1). In these
cases, the number of PPHA cells overlapped with those in the MDS
group. Therefore, the proportion of circulating PPHA cells
Image 4 (Case 7, Table 2) Clonal cytogenetic abnormality
detected by chromosomal karyotyping. Representative karyotype
showing an apparently balanced translocation between the X
chromosome and chromosome 5. The International System for Human
Cytogenetic Nomenclature describing this clonal abnormality is as
follows: 46,X,t(X;5)(q13;q32)[10]/46,XX[11]. In this case, mild
dysplasia and hypercellularity were noted by morphologic
examination of the bone marrow biopsy specimen, and the presence of
a clonal cytogenetic abnormality confirmed the diagnosis of
myelodysplastic syndrome.
Table 2Evaluation of MDS With Component of PPH Anomaly*
CBC Marrow
Case No./ WBCs Neutrophils Hemoglobin Platelets Blasts PPH
BlastsSex/Age (y) History ( 109/L) ( 109/L) (g/L) ( 109/L) (%)
Cells (%) Cellularity (%) Dysplasia Cytogenetics Classification
1/M/75 Cytopenia 2.5 0.52 100 59 24 Hyper 7 Marked 46,XY
RAEB2/F/61 Anemia 6.0 NA 69 143 3 Hyper 8 Marked Complex RAEB3/M/53
Anemia 3.5 2.24 116 229 4 Norm
-
300 Am J Clin Pathol 2011;135:291-303300 DOI:
10.1309/AJCPVFY95MAOBKRS
American Society for Clinical Pathology
Wang et al / PseudoPelger-Hut Anomaly Induced by Medications
morphologic dysplasia other than PPHA. All cases demon-strated
at least 2 additional bone marrow abnormalities that were
diagnostic or suggestive of MDS (Table 2), whereas none of these
additional pathologic features were present in the iatrogenic PPHAs
except for 2 CLL cases (hypercel-lularity in case 10 and
hypercellularity/complex cytogenetic abnormality in case 11; Table
1) in which the abnormalities were apparently related to the
underlying CLL. Thus, our analysis shows a tendency for clustered
pathologic abnormali-ties in MDS-related PPHA, which can aid in the
distinction from iatrogenic PPHA. Nevertheless, our selective
subset of MDS cases shows pathologic abnormalities more frequent
than those in MDS in general.26,27 This selection bias may be
explained by the fact that PPHA represents a severe degree of
dysplasia in cases of MDS, and, thus, its presence tends to be
associated with other pathologic abnormalities related to MDS.
Based on this comparative study, we propose a diag-nostic algorithm
for workup of cases in which PPHA cells are identified in
peripheral blood or bone marrow aspirate smears Figure 2. In this
algorithm, acquired or pseudo-PHA (PPHA) is suggested if the
patient had normal neutrophilic segmentation in the past. PPHA with
normal peripheral blood cell counts would suggest a reversible
(benign) change, par-ticularly in organ and bone marrow transplant
recipients, or in patients currently taking medications known to
induce PPHA and with a high proportion of PPHA cells. Otherwise,
MDS or a related myeloid neoplasm should be considered and should
be excluded by additional tests. In cases of bone marrow or
hematopoietic stem cell transplantation, donor engraftment would
suggest a donor origin of PPHA, which is likely to be reversible or
benign but still needs to be confirmed by the absence of other
pathologic abnormalities diagnostic or suggestive of a myeloid
neoplasm. The optimal evidence of the benign nature of iatrogenic
PPHA would be spontaneous resolution of PPHA cells, normalization
of neutrophilic seg-mentation, or altered proportions of PPHA cells
in correlation with dose adjustment of relevant medications.
An isolated PPHA (without other pathologic abnormali-ties
related to MDS or other myeloid neoplasms), particularly with high
proportions of PPHA cells (typically >30%) escalat-ing within a
short time, is indicative of benign or reversible PPHA unless
proven otherwise.
A fairly extensive number of drugs has been associated with the
occurrence of PPHA Table 3. Of note, along with the rise in organ
and hematopoietic stem cell transplantation in the past decade,
cases of iatrogenic PPHA have become more frequent in hematology
clinics and/or clinical laborato-ries, with some resulting in bone
marrow biopsies to exclude MDS or related myeloid neoplasms. PPHA
in transplant recipients has been related to 2 immunosuppressive
drugs, mycophenolate mofetil7-9 and tacrolimus.7,10 Indeed, of the
13 iatrogenic PPHA cases in our series, 9 (69%) were treated
cases with morphologically low- to intermediate-risk MDS (cases
3, 4, 5, 7, 8, and 9; Table 2) had clonal cytogenetic abnormalities
detected. Of 7 cases with clonal cytogenetic abnormalities, 3 were
in a poor prognostic category and 4 were in an intermediate
category according to the International Prognostic Scoring System
for MDS.21 All but 1 case showed
0200
X
400600800
1,000100
AM vWA D8S1179 TPOX FGA
140 180 220 260 300 340
14 14 8 12 2022
18Y
0200
X
400600800
1,000100
AM vWA D8S1179 TPOX FGA
140 180 220 260 300 340
14 8 2225
18Y 16 10
0200
X
400600800
1,000100
AM vWA D8S1179 TPOX FGA
140 180 220 260 300 340
14 8 2225
18Y 16 10
A
B
C
Figure 1 (Case 1, Table 1) Bone marrow engraftment study
demonstrating donor cell engraftment in a hematopoietic stem cell
recipient when 94% pseudoPelger-Hut anomaly cells were identified
in the peripheral blood. Short tandem repeat (STR) genotype profile
of pretransplantation/recipient (A), donor (B), and
posttransplantation CD15+ cells (C). The letters and numbers in the
boxes above each block indicate the names of STR markers, and the
numbers below indicate the numbers of repeats for each STR marker.
Note a complete match of 4 STR loci between donors (B) and
posttransplant recipients CD15+ cells (C). AM indicates the
amelogenin gene, which is used here for sex determination and DNA
quality control. The X chromosome gene, AMELX, gives rise to a 106
base pair amplicon (indicated by X in the box) and the Y chromosome
gene, AMELY, a 112 base pair amplicon (indicated by Y in the
box).
-
Am J Clin Pathol 2011;135:291-303 301301 DOI:
10.1309/AJCPVFY95MAOBKRS 301
American Society for Clinical Pathology
Hematopathology / Original Article
with mycophenolate mofetil, and 8 of these patients received
tacrolimus as well.
Concomitant use of the antiviral drug gancyclovir9 or antifungal
drug fluconazole10 has also been suggested to have a role in
development of PPHA in transplant recipients, prob-ably via
drug-drug interactions or altered enzymatic activities involving
the metabolic pathway of transplant medications. In all reported
cases, the morphologic changes in neutrophils appear reversible
because PPHA cells are decreased follow-ing dose adjustment of
transplant medications or disappear after discontinuation of the
relevant drugs.7-10 Generally, in transplant recipients, a
resolution of neutrophilic abnormal-ity occurs 2 to 6 weeks after
adjustment or cessation of the relevant medications.7,10
In our series, 2 of 9 patients treated with transplant
medications (cases 1 and 7 among cases 1-9, including case 6 of
autoimmune disease treated with mycophenolate mofetil) resumed
normal neutrophilic segmentation following dose adjustment of
immunosuppressive drugs. The remaining 7 cases showed spontaneous
resolution of PPHA cells without change of relevant medications,
which may be explained by a drug desensitization or tolerance. This
desensitization might not be permanent, as illustrated in case 8,
in which following a transient and spontaneous decrease in PPHA
cells, a recur-rence of these cells to high numbers was noted
during an epi-sode of renal failure, perhaps related to increased
serum drug levels due to lack of renal excretion. Why the 2 cases
with changes of PPHA related to dose adjustment of medications had
longer intervals for the resolution is unclear, but it may be due
to failure to desensitize and the persistence of PPHA until
adjustment of medications for other medical issues. Of 3 CLL cases,
1 patient (case 10) was receiving co-trimoxazole
PHA
No
No
No
No
No
No
No
Needsconfirming
Confirmed
No
Yes
Yes
YesYes
Yes
Yes
No
Yes
Yes
Prior normalsegmentation?
Acquired/PPHA
Cytopenia?
Transplant/otherrelevant medications? Possible MDS
Work up forhereditary PHA
BMT? Cytogenetics?
Engraftment? Increasedblasts?
Possiblereversible
PPHA
Other dysplasia?
Spontaneousdecrease
in PHA
Figure 2 Diagnostic algorithm for pseudoPelger-Hut anomaly
(PPHA) identified in a peripheral blood smear or/and bone marrow
aspirate smear. BMT, bone marrow transplantation; MDS,
myelodysplastic syndrome; PPHA, Pelger-Hut anomaly.
Table 3Medications Associated With PseudoPelger-Hut Anomaly as
Reported in the Literature
Drug Trade or Other Name Pharmacologic Action Indication Effect
ReferenceMycophenolate CellCept Immunosuppression Organ
transplantation D Etzell and Wang,7 Asmis mofetil et al,8 Kennedy
et al9Tacrolimus Prograf; FK-506 Immunosuppression Organ
transplantation D/I Etzell and Wang,7 Gondo et al10Valproate
Depakote, Depacon Inhibition of GABA Bipolar disorders, D May and
Sunder15 or Stavzor transaminase seizuresSulfisoxazole Gantrisin;
sulfafurazole Antibiotic Bacterial infection D Kaplan and
Barrett14Ganciclovir Cytovene; Cymevene Antiviral DNA polymerase
Viral infection I Kennedy et al9Fluconazole Diflucan; Trican
Antifungal cytochrome P450 Fungal infection I Gondo et
al10Ibuprofen Advil; Motrin; Nurofen Inhibition of cyclooxygenase
Rheumatoid conditions; pain D Moreira et al13 Paclitaxel Taxol
Antimitosis Cancer D Juneja et al11Docetaxel Taxotere Antimitosis
Cancer D Juneja et al11G-CSF (filgrastim) Neupogen Growth factor
Neutropenia D Teshima et al12GM-CSF Sargramostim; Leukine; Growth
factor Leukopenia D Teshima et al12 (molgramostim)
LeucomaxColchicine Colcrys Antimitosis Gout D Clevenger et al17
D-penicillamine Cuprimine; Depen Immunosuppression Rheumatoid
conditions D Levin16D, direct; GABA, -aminobutyric acid; G-CSF,
granulocyte colony-stimulating factor; GM-CSF, granulocyte-monocyte
colony-stimulating factor; I, indirect or via drug-drug
interaction.
-
302 Am J Clin Pathol 2011;135:291-303302 DOI:
10.1309/AJCPVFY95MAOBKRS
American Society for Clinical Pathology
Wang et al / PseudoPelger-Hut Anomaly Induced by Medications
California Keck School of Medicine, Los Angeles; 3Laboratory
Medicine, UCSF/VA Medical Center, San Francisco, CA; and
4Pathology, City of Hope National Medical Center, Duarte, CA.
Presented in part at the 99th Annual Meeting of the United
States and Canadian Academy of Pathology; Washington, DC; March
20-26, 2010.
Address reprint requests to Dr Wang: Dept of Pathology, DUMC Box
3712, M-345 Davison Bldg (Green Zone), Duke Hospital South, Durham,
NC 27710.
Acknowledgment: We thank Steven R. Conlon, Department of
Pathology, Duke University School of Medicine, for technical
assistance with the photo images.
References 1. Pelger K. Demonstrate van een paar zeldzaam
voorkomende
typen van bloedlichaampjes en bespreking der patienten. Ned
Tijdschr Geneeskd. 1928;72:1178.
2. Hut GJ. Familiaire anomalie der leucocyten. Ned Tijdschr
Geneeskd. 1931;75:5956-5959.
3. Speeckaert MM, Verhelst C, Koch A, et al. Pelger-Hut anomaly:
a critical review of the literature. Acta Haematol.
2009;121:202-206.
4. Cunningham JM, Patnaik MM, Hammerschmidt DE, et al.
Historical perspective and clinical implications of the Pelger-Het
cell. Am J Hematol. 2009;84:116-119.
5. Cunningham I, MacCallum SJ, Nicholls MD, et al. The
myelodysplastic syndromes: an analysis of prognostic factors in 226
cases from a single institution. Br J Haematol.
1995;90:602-606.
6. Kuriyama K, Tomonaga M, Matsuo T, et al. Diagnostic
significance of detecting pseudo-Pelger-Hut anomalies and
micro-megakaryocytes in myelodysplastic syndrome. Br J Haematol.
1986;63:665-669.
7. Etzell JE, Wang E. Acquired Pelger-Hut anomaly in association
with concomitant tacrolimus and mycophenolate mofetil in a liver
transplant patient: a case report and review of the literature.
Arch Pathol Lab Med. 2006;130:93-96.
8. Asmis LM, Hadaya K, Majno P, et al. Acquired and reversible
Pelger-Hut anomaly of polymorphonuclear neutrophils in three
transplant patients receiving mycophenolate mofetil therapy. Am J
Hematol. 2003;73:244-248.
9. Kennedy GA, Kay TD, Johnson DW, et al. Neutrophil dysplasia
characterised by a pseudo-Pelger-Hut anomaly occurring with the use
of mycophenolate mofetil and ganciclovir following renal
transplantation: a report of five cases. Pathology.
2002;34:263-266.
10. Gondo H, Okamura C, Osaki K, et al. Acquired Pelger-Hut
anomaly in association with concomitant tacrolimus and fluconazole
therapy following allogeneic bone marrow transplantation. Bone
Marrow Transplant. 2000;26:1255-1257.
11. Juneja SK, Matthews JP, Luzinat R, et al. Association of
acquired Pelger-Hut anomaly with taxoid therapy. Br J Haematol.
1996;93:139-141.
12. Teshima T, Shibuya T, Harada M, et al. Effects of G-CSF,
GM-CSF, and IL-5 on nuclear segmentation of neutrophils and
eosinophils in congenital or acquired Pelger-Hut anomaly. Exp
Hematol. 1991;19:322-325.
13. Moreira AM, Vieira LM, Rios DR, et al. Acquired Pelger-Hut
anomaly associated with ibuprofen therapy [letter] [published
correction appears in Clin Chim Acta. 2010;411:1397]. Clin Chim
Acta. 2009;409:140-141.
bendamustine, ciprofloxacin, and other drugs, while the other 2
patients (cases 11 and 12) were treated with fludarabine and
rituximab, in addition to several other drugs. While the
sul-fonamide component sulfamethoxazole in Bactrim may have a role
in the formation of PPHA in the former (case 10), con-comitant use
of other medications complicates the analysis of the causative
factors. No drug listed in Table 3 was noted to be used in the
other 2 cases of CLL (cases 11 and 12). Although both patients were
taking fludarabine and rituximab, suggest-ing possible causality,
PPHA has been described historically in CLL, even before these 2
drugs were introduced.28,29
Clinical observations of change in neutrophilic segmenta-tion in
correlation with dose adjustment of certain drugs should be able to
identify the causative regimens in these cases. Case 13 was a
patient who was administered granulocyte colony-stimulating factor
(a drug listed in Table 3) at the time when circulating PPHA was
noted in peripheral blood and aspirate smears. Owing to the
complexity of numerous medications in each case (ranging from 10 to
26 drugs when PPHA was iden-tified in the peripheral blood), it is
difficult to ascertain the exact role of individual drug(s) or
which one might be essen-tial for the development of PPHA in our
cases. Actually, in a clinical setting, it would not be practical
to allow a complete cessation or even a dose reduction of relevant
medications to test the causative effect strictly for investigative
purposes owing to the risk of losing grafts or other potential
compli-cations. Therefore, pathologic exclusion of MDS or related
myeloid neoplasms has a central role in defining the benign nature
of iatrogenic PPHA in these cases.
The underlying mechanism of PPHA induced by medica-tions is
unclear. Hoffmann et al30 discovered the linkage of hereditary PHA
to the lamin B-receptor (LBR) gene located on the long arm of
chromosome 1 (1q41-43) by using mi-crosatellite-based genetic
linkage analysis. They also found a gene dose-dependent reduction
of LBR protein, the quantity of which is inversely correlated with
severity of neutrophilic hypolobation or hyposegmentation. LBR is
an integral protein component of the inner nuclear membrane and
seems to inter-act with lamin B and heterochromatin to affect
nuclear loba-tion. While the reversible nature of PPHA induced by
medica-tions does not suggest a permanent change or mutation of the
LBR gene, certain drugs may have a role in down-regulation of LBR
gene expression or may interact directly with LBR protein to block
its function. In addition, future investigations regard-ing the
mutation status of the LBR gene in cases of PPHA sec-ondary to MDS
or related myeloid neoplasms might provide an additional genetic
marker for diagnosis of these neoplasms, which may also enable a
more definitive distinction between myeloid neoplasiarelated and
iatrogenic PPHA.
From the Departments of 1Pathology, Duke University Medical
Center, Durham, NC; 2Pathology, University of Southern
-
Am J Clin Pathol 2011;135:291-303 303303 DOI:
10.1309/AJCPVFY95MAOBKRS 303
American Society for Clinical Pathology
Hematopathology / Original Article
24. Shetty V, Hussaini S, Broady-Robinson L, et al.
Intramedullary apoptosis of hematopoietic cells in myelodysplastic
syndrome patients can be massive: apoptotic cells recovered from
high-density fraction of bone marrow aspirates. Blood.
2000;96:1388-1392.
25. Shetty V, Hussaini S, Alvi S, et al. Excessive apoptosis,
increased phagocytosis, nuclear inclusion bodies and cylindrical
confronting cisternae in bone marrow biopsies of myelodysplastic
syndrome patients. Br J Haematol. 2002;116:817-825.
26. Chatterjee T, Dixit A, Mohapatra M, et al. Clinical,
haematological and histomorphological profile of adult
myelodysplastic syndrome: study of 96 cases in a single institute.
Eur J Haematol. 2004;73:93-97.
27. Jotterand-Bellomo M, Parlier V, Schmidt PM, et al.
Cytogenetic analysis of 54 cases of myelodysplastic syndrome.
Cancer Genet Cytogenet. 1990;46:157-172.
28. Liesveld J, Smith BD. Acquired Pelger-Hut anomaly in a case
of non-Hodgkins lymphoma. Acta Haematol. 1988;79:46-49.
29. Kornberg A, Goldfarb A, Shalev O. PseudoPelger-Hut anomaly
in chronic lymphocytic leukemia. Acta Haematol.
1981;66:127-128.
30. Hoffmann K, Dreger CK, Olins AL, et al. Mutations in the
gene encoding the lamin B receptor produce an altered nuclear
morphology in granulocytes (Pelger-Hut anomaly). Nat Genet.
2002;31:410-414.
14. Kaplan JM, Barrett O Jr. Reversible pseudo-Pelger anomaly
related to sulfisoxazole therapy. N Engl J Med.
1967;277:421-422.
15. May RB, Sunder TR. Hematologic manifestations of long-term
valproate therapy. Epilepsia. 1993;34:1098-1101.
16. Levin JM. Pelger-Hut anomaly and d-penicillamine [letter]. J
Rheumatol. 1980;7:418-419.
17. Clevenger CV, August TF, Shaw LM. Colchicine poisoning:
report of a fatal case with body fluid analysis by GC/MS and
histopathologic examination of postmortem tissues. J Anal Toxicol.
1991;15:151-154.
18. Cicchitto G, Parravicini M, De Lorenzo S, et al.
Tuberculosis and Pelger-Hut anomaly: case report. Panminerva Med.
1999;41:367-369.
19. Rosell Arnold E, Rodrguez Migulez JM, Roquer Gonzlez JM, et
al. Reversible Pelger-Het anomaly associated with acute
gastroenteritis caused by salmonella group D [in Spanish]. An Esp
Pediatr. 1989;30:143-144.
20. van Hook L, Spivack C, Duncanson FP. Acquired Pelger-Hut
anomaly associated with Mycoplasma pneumoniae pneumonia. Am J Clin
Pathol. 1985;84:248-251.
21. Brunning RD, Orazi A, Germing U, et al. Myelodysplastic
syndromes. In: Swerdlow SH, Campo E, Harris NL, et al, eds. WHO
Classification of Tumours of Haematopoietic and Lymphoid Tissues.
4th ed. Lyon, France: IARC Press; 2008:88-107.
22. Hartsock RJ, Smith EB, Petty CS. Normal variations with
aging of the amount of hematopoietic tissue in bone marrow from the
anterior iliac crest: a study made from 177 cases of sudden death
examined by necropsy. Am J Clin Pathol. 1965;43:326-331.
23. Shetty VT, Mundle SD, Raza A. Pseudo Pelger-Hut anomaly in
myelodysplastic syndrome: hyposegmented apoptotic neutrophil?
Blood. 2001;98:1273-1275.