Imaging of fulminant infections in diabetic patients

Imaging of fulminant Imaging of fulminant infections in diabetic infections in diabetic

patientspatients

Dr/Ahmed BahnassyDr/Ahmed Bahnassy

Assistant Professor of RadiologyAssistant Professor of Radiology

College of Medicine- Qassim College of Medicine- Qassim UniversityUniversity

Diagnostic considerations in Diagnostic considerations in fulminant infections in diabetic fulminant infections in diabetic

patients.patients. Low immuneLow immune state of these patients. state of these patients. Susceptibility to infections ..including Susceptibility to infections ..including

fungifungi, and virulent , and virulent gram negativegram negative organismorganism

ExtensionExtension to surrounding soft tissues to surrounding soft tissues and bones .and bones .

Similarity to Similarity to malignantmalignant diseases . diseases . Potential Potential lethal outcomelethal outcome..

Therefore :diagnostic evaluation of Therefore :diagnostic evaluation of an infection in diabetic patient is an infection in diabetic patient is three folds:three folds:

1.To locate the primary site of 1.To locate the primary site of infection.infection.

2.To study the local extension of this 2.To study the local extension of this infection.infection.

3.To suggest the causative organism 3.To suggest the causative organism to take into consideration its to take into consideration its behavior and its appropriate behavior and its appropriate treatment .treatment .

I-Head and neck I-Head and neck infectionsinfections

A-Malignant Otitis ExternaA-Malignant Otitis Externa

Severe life threatening infection of Severe life threatening infection of external auditory canal and surrounding external auditory canal and surrounding tissues.tissues.

Most common organism is Pseudomonas Most common organism is Pseudomonas AeruginosaAeruginosa

C/O: unrelenting C/O: unrelenting otalgia,headache.purulent otorrhea otalgia,headache.purulent otorrhea unresponsive to topical antibiotics.unresponsive to topical antibiotics.

Location : at bone cartilage junction of Location : at bone cartilage junction of EAC.EAC.

Extension of infectionExtension of infection

Inferiorly into soft issues inferior to Inferiorly into soft issues inferior to temporal bone, parotid space and temporal bone, parotid space and nasopharyngeal masticator space nasopharyngeal masticator space

Posteriorly into mastoidPosteriorly into mastoid

Anteriorly into temporomandibular Anteriorly into temporomandibular joint .joint .

And Medially into petrous apexAnd Medially into petrous apex

Mucormycosis is an Mucormycosis is an aggressive, opportunistic aggressive, opportunistic infection caused by fungi .infection caused by fungi .

In individuals who are In individuals who are immunocompromised, immunocompromised, germination and hyphae germination and hyphae formation occur, and this formation occur, and this allows the organism to allows the organism to invade the patient's blood invade the patient's blood vessels. vessels.

B-MucormycosisB-Mucormycosis

Extension of infectionExtension of infection

Sinus Mucormycosis with Sinus Mucormycosis with orbital extensionorbital extension

Pterygopalatine fossa Pterygopalatine fossa extensionextension

Intraorbital Extension Intraorbital Extension

Intracranial extension Intracranial extension

cavernous sinus Thrombosis cavernous sinus Thrombosis

C-Other fungal infections -C-Other fungal infections -Sinus AspergillosisSinus Aspergillosis

D-Orbital infectionsD-Orbital infections

Orbital infections most often occur Orbital infections most often occur secondarily to an underlying paranasal secondarily to an underlying paranasal sinusitis; The two paranasal sinuses sinusitis; The two paranasal sinuses most often involved in orbital infections most often involved in orbital infections are the are the ethmoid and maxillary sinusesethmoid and maxillary sinuses. . Spread of infection from the sinuses to Spread of infection from the sinuses to the orbit may occur directly through the orbit may occur directly through extension via the osseous structures or extension via the osseous structures or indirectly through the valveless venous indirectly through the valveless venous plexus surrounding the orbit and plexus surrounding the orbit and paranasal sinuses . paranasal sinuses .

Subperiosteal abscess Subperiosteal abscess

Infection from the sinus may extend Infection from the sinus may extend into and involve the subperiosteum, into and involve the subperiosteum, intraconal and extraconal spaces, intraconal and extraconal spaces, and the globe. and the globe.

A subperiosteal abscess (SPA) results A subperiosteal abscess (SPA) results from the development of purulent from the development of purulent material between the orbital bones material between the orbital bones and periorbita. and periorbita.

Location of infection:Location of infection: Preseptal Preseptal =periorbital =periorbital

soft tissue.soft tissue. Subperiosteal Subperiosteal ;periph;periph

eral =eral =extraconal extraconal fat;extraocular fat;extraocular muscle;centralmuscle;central =intraconal fat;=intraconal fat;optic optic nerve nerve complexcomplex ; ;globe;lacriglobe;lacrimal glandmal gland . .

II-Chest II-Chest InfectionsInfections

A-AspergillosisA-Aspergillosis

Pulmonary aspergillosis is a spectrum of Pulmonary aspergillosis is a spectrum of mycotic diseases caused by mycotic diseases caused by AspergillusAspergillus species, usually species, usually Aspergillus fumigatus.Aspergillus fumigatus. This intensely antigenic and ubiquitous This intensely antigenic and ubiquitous soil fungus is commonly found in the soil fungus is commonly found in the sputum of healthy individuals. However, sputum of healthy individuals. However, in susceptible hosts, its ability to invade in susceptible hosts, its ability to invade the arteries and veins facilitates its the arteries and veins facilitates its hematogenous spread. hematogenous spread.

FormsForms Pulmonary aspergillosis may take any of 4 forms: Pulmonary aspergillosis may take any of 4 forms: Allergic bronchopulmonary aspergillosis (ABPA) Allergic bronchopulmonary aspergillosis (ABPA)

is caused by a hypersensitivity reaction to the is caused by a hypersensitivity reaction to the fungus . fungus .

Saprophytic aspergillosis, or aspergilloma, is the Saprophytic aspergillosis, or aspergilloma, is the most common form. This form is noninvasive and most common form. This form is noninvasive and involves colonization of preexisting cavities. involves colonization of preexisting cavities.

Chronic necrotizing aspergillosis, also called Chronic necrotizing aspergillosis, also called semi-invasive aspergillosis, is a chronic cavitary semi-invasive aspergillosis, is a chronic cavitary pneumonic illness that often affect patients with pneumonic illness that often affect patients with preexisting chronic lung disease. preexisting chronic lung disease.

Angioinvasive aspergillosis which is often fatal.Angioinvasive aspergillosis which is often fatal.

Aspegillosis :Invasive Aspegillosis :Invasive Aspergillosis -Halo Sign Aspergillosis -Halo Sign

Patchy Patchy consolidations consolidations with with surrounding surrounding area of ground area of ground glass opacity glass opacity describes the describes the halo sign in halo sign in Angio-invasive Angio-invasive form of form of aspergillosisaspergillosis

Angio -invasive Aspergillosis Angio -invasive Aspergillosis with air crescent sign.with air crescent sign.

Semi-Invasive AspegillosisSemi-Invasive Aspegillosis Mild Mild

immunocompimmunocompromiseromise

Consolidation Consolidation ,cavitation ,Pl,cavitation ,Pleural eural thickening ,thickening ,+/-mass +/-mass within the within the cavity )cavity )

III-Abdominal III-Abdominal InfectionsInfections

A-Emphysematous A-Emphysematous cholecystitischolecystitis

Ischaemia +infection Ischaemia +infection with gas producing with gas producing organisms.organisms.

Organism:ClostridiuOrganism:Clostridium Welchii,Ecoli.m Welchii,Ecoli.

1/3 show normal 1/3 show normal WBC.WBC.

Point tenderness is Point tenderness is rarerare due to diabetic due to diabetic neuropathyneuropathy

15% mortality15% mortality

B-Emphysematous B-Emphysematous PyelonephritisPyelonephritis

Emphysematous Emphysematous pyelonephritis (EPN) is pyelonephritis (EPN) is a life-threatening, a life-threatening, fulminant, necrotizing fulminant, necrotizing upper urinary tract upper urinary tract infection associated infection associated with gas within the with gas within the kidney and/or kidney and/or perinephric space. perinephric space.

organisms : organisms : E. coliE. coli (68%), (68%), Klebsiella Klebsiella pneumoniaepneumoniae (9%), and (9%), and Proteus mirabilis.Proteus mirabilis.

C-Emphysematous cystitisC-Emphysematous cystitis

UT infection by gas UT infection by gas forming organism forming organism almost almost pathognomonic of pathognomonic of poorly controlled poorly controlled diabetes .diabetes .

Organism: Organism: E.coli,E.aerogenes.E.coli,E.aerogenes.

CT is the most CT is the most sensitive sensitive examination.examination.

D-Xanthogranulomatous D-Xanthogranulomatous PyelonephritisPyelonephritis

Xanthogranulomatous Xanthogranulomatous pyelonephritis (XGPN) pyelonephritis (XGPN) represents an unusual represents an unusual suppurative suppurative granulomatous reaction granulomatous reaction to chronic infection, to chronic infection, often in the presence of often in the presence of chronic obstruction .chronic obstruction .

Two forms of XGPN are Two forms of XGPN are described, namely, a described, namely, a diffuse or global form diffuse or global form (83-90% of patients) and (83-90% of patients) and a focal form (10-17%). a focal form (10-17%).

a polymicrobial necrotizing fasciitis of a polymicrobial necrotizing fasciitis of the perineal, perirectal or genital the perineal, perirectal or genital areaarea . .

500 reported cases in literature .500 reported cases in literature .

E-Fournier Gangrene E-Fournier Gangrene

Radiological diagnosisRadiological diagnosis

Radiographs can show the presence of soft Radiographs can show the presence of soft tissue gas in patients suspected of having tissue gas in patients suspected of having necrotizing fasciitis.necrotizing fasciitis.

SSonographic evaluation of the scrotum, onographic evaluation of the scrotum, scrotal contents, and surrounding structures scrotal contents, and surrounding structures shows a thickened and oedematous scrotal shows a thickened and oedematous scrotal wall, gas within the scrotal wall, and wall, gas within the scrotal wall, and unilateral or bilateral peritesticular fluid. unilateral or bilateral peritesticular fluid. Subcutaneous gas within the scrotal wall is Subcutaneous gas within the scrotal wall is the sonographic hallmark.the sonographic hallmark.

Radiological findingsRadiological findings

Note gas lucencies Note gas lucencies in scrotal in scrotal subcutaneous subcutaneous tissuetissue

Air loculi seen as Air loculi seen as highly reflecting highly reflecting ring shadows.ring shadows.

ConclusionConclusion

Infections in diabetic patients have Infections in diabetic patients have many many specificspecific considerations in their considerations in their diagnosis.diagnosis.

Their Their extensions extensions increase the increase the seriousness of the condition .seriousness of the condition .

The The potential lethalpotential lethal outcome of these outcome of these cases must prompt a rapid and cases must prompt a rapid and accurate diagnosis .accurate diagnosis .

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