This document discusses diagnostic considerations for fulminant infections in diabetic patients. It notes that these patients have low immunity and are susceptible to aggressive infections. Imaging is important to locate the infection site, assess extension, and suggest causative organisms. Several specific infection types are described in detail for the head/neck, chest, and abdomen that commonly affect diabetics, including mucormycosis, aspergillosis, emphysematous infections, and Fournier gangrene. Radiography and other imaging can help diagnose these infections and determine severity. An accurate, rapid diagnosis is important given the potential lethality of these infections in diabetics.

1. Imaging of fulminant
infections in diabetic
patients
Dr/Ahmed Bahnassy
Assistant Professor of Radiology
College of Medicine- Qassim University

2. Diagnostic considerations in fulminant
infections in diabetic patients.
 Low immune state of these patients.
 Susceptibility to infections ..including
fungi, and virulent gram negative organism
 Extension to surrounding soft tissues and
bones .
 Similarity to malignant diseases .
 Potential lethal outcome.

3.  Therefore :diagnostic evaluation of an
infection in diabetic patient is three folds:
 1.To locate the primary site of infection.
 2.To study the local extension of this
infection.
 3.To suggest the causative organism to
take into consideration its behavior and its
appropriate treatment .

4. I-Head and neck
infections

5. A-Malignant Otitis Externa
 Severe life threatening infection of external
auditory canal and surrounding tissues.
 Most common organism is Pseudomonas
Aeruginosa
 C/O: unrelenting otalgia,headache.purulent
otorrhea unresponsive to topical antibiotics.
 Location : at bone cartilage junction of EAC.

6. Extension of infection
 Inferiorly into soft issues inferior to
temporal bone, parotid space and
nasopharyngeal masticator space

7.  Posteriorly into mastoid

8.  Anteriorly into temporomandibular joint .

9.  And Medially into petrous apex

10. B-Mucormycosis
 Mucormycosis is an aggressive,
opportunistic infection caused by
fungi .
 In individuals who are
immunocompromised,
germination and hyphae
formation occur, and this allows
the organism to invade the
patient's blood vessels.

11. Extension of infection

12. Sinus Mucormycosis with orbital
extension

13. Pterygopalatine fossa extension

14. Intraorbital Extension

15. Intracranial extension

16. cavernous sinus Thrombosis

17. C-Other fungal infections -Sinus
Aspergillosis

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

19. Subperiosteal abscess
 Infection from the sinus may extend into
and involve the subperiosteum, intraconal
and extraconal spaces, and the globe.
 A subperiosteal abscess (SPA) results
from the development of purulent material
between the orbital bones and periorbita.

20.  Location of infection:
 Preseptal =periorbital
soft tissue.
 Subperiosteal
;peripheral
=extraconal
fat;extraocular
muscle;central
=intraconal fat;optic
nerve complex
;globe;lacrimal gland .

21. II-Chest Infections

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

23. Forms
 Pulmonary aspergillosis may take any of 4 forms:
 Allergic bronchopulmonary aspergillosis (ABPA) is
caused by a hypersensitivity reaction to the fungus .
 Saprophytic aspergillosis, or aspergilloma, is the most
common form. This form is noninvasive and involves
colonization of preexisting cavities.
 Chronic necrotizing aspergillosis, also called semi-
invasive aspergillosis, is a chronic cavitary pneumonic
illness that often affect patients with preexisting
chronic lung disease.
 Angioinvasive aspergillosis which is often fatal.

24. Aspegillosis :Invasive Aspergillosis
-Halo Sign
 Patchy
consolidations
with surrounding
area of ground
glass opacity
describes the
halo sign in
Angio-invasive
form of
aspergillosis

25. Angio -invasive Aspergillosis with
air crescent sign.

26. Semi-Invasive Aspegillosis
 Mild
immunocompro
mise

Consolidation ,
cavitation
,Pleural
thickening ,+/-
mass within the
cavity )

27. III-Abdominal
Infections

28. A-Emphysematous cholecystitis
 Ischaemia +infection
with gas producing
organisms.
 Organism:Clostridium
Welchii,Ecoli.
 1/3 show normal WBC.
 Point tenderness is
rare due to diabetic
neuropathy
 15% mortality

29. B-Emphysematous Pyelonephritis
 Emphysematous
pyelonephritis (EPN) is a
life-threatening,
fulminant, necrotizing
upper urinary tract
infection associated with
gas within the kidney
and/or perinephric space.
 organisms : E. coli
(68%), Klebsiella
pneumoniae (9%), and
Proteus mirabilis.

30. C-Emphysematous cystitis
 UT infection by gas
forming organism
almost
pathognomonic of
poorly controlled
diabetes .
 Organism:
E.coli,E.aerogenes.
 CT is the most
sensitive examination.

31. D-Xanthogranulomatous
Pyelonephritis
 Xanthogranulomatous
pyelonephritis (XGPN)
represents an unusual
suppurative granulomatous
reaction to chronic infection,
often in the presence of
chronic obstruction .
 Two forms of XGPN are
described, namely, a diffuse
or global form (83-90% of
patients) and a focal form
(10-17%).

32. E-Fournier Gangrene
 a polymicrobial necrotizing fasciitis of the
perineal, perirectal or genital area .
 500 reported cases in literature .

33. Radiological diagnosis
 Radiographs can show the presence of soft
tissue gas in patients suspected of having
necrotizing fasciitis.
 Sonographic evaluation of the scrotum, scrotal
contents, and surrounding structures shows a
thickened and oedematous scrotal wall, gas
within the scrotal wall, and unilateral or bilateral
peritesticular fluid. Subcutaneous gas within the
scrotal wall is the sonographic hallmark.

34. Radiological findings
 Air loculi seen as
highly reflecting ring
shadows.
 Note gas lucencies in
scrotal subcutaneous
tissue

35. Conclusion
 Infections in diabetic patients have many
specific considerations in their diagnosis.
 Their extensions increase the seriousness
of the condition .
 The potential lethal outcome of these
cases must prompt a rapid and accurate
diagnosis .

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