Coinfection of mucormycosis and aspergillus in a diabetic patient: A rare entity:

Introduction

Mucormycosis is an opportunistic, aggressive infection caused by organisms belonging to Mucorales order of the class Zygomycetes. They are saprophytes and are universally distributed. Aspergillosis is the clinical condition caused by the Aspergillus species, most often A. fumigates.1 The predisposing conditions for both the organisms are uncontrolled diabetes, immunodeficiency, organ transplantation, underlying malignancy and cirrhosis.2 If diagnosis and therapeutic interventions are delayed it may result in massive tissue destruction and, eventually death. A very few case reports of coinfection of mucormycosis and aspergillus in a diabetic are described in the literature.3

Case Report

A 60-yrs-old female presented with headache in left frontal region, left nasal obstruction and left sided purulent nasal discharge for last one and half month. Headache was relieved with medication. There was a history of single episode of epistaxis and diminution of vision for last 20 days. The patient was known case of uncontrolled diabetes.

Blood test revealed anemia, leucocytosis and increased ESR (Hb-10.0 g/dl, TLC-126000 cells/ cumm, ESR- 116 mm in 1^st hour). Blood sugar was 276 mg/dl. Liver function test and renal function test were within normal limits. She was HIV 1 and HIV 2 nonreactive NCCT PNS revealed left maxillary, ethmoid, frontal and sphenoid sinusitis with mucosal thinning and froathing secretions in left nasal cavity with bony erosions of the walls of left maxillary.

Surgical debridement was done under general anaesthesia which showed black crusts and necrosed nasal septum. Histopathology sections showed numerous broad aseptate ribbon like hyphae of mucor along with thin septate aspergillus hyphae with acute angle branching (Figure 1,Figure 2). Many sporangiospores and occasional fruity bodies of aspergillus were also noted which are very rarely seen on histology sections. These hyphae, spore and fruity bodies were highlighted on silver stain (Figure 3). However, on nasal KOH mount only broad hyphae with branching were noted.

Patient was started on liposomal amphotericn B, a cumulative dose of 2000 mg was given, followed by itraconazole 200 mg OD. While on amphotericin she developed hypokalemia for which syrup pottasiun chloride was given. One unit of packed cell blood transfusion was done to correct anemia.

Patient responded well and was free of symptoms at the time of discharge.

Here we have presented a very rare combination of aspergillus with mucor infection alongwith presence of fruity bodies which are hardly seen on histopathology.

Figure 1

Section showing angioinvasion by the fungal hyphae. (Arrow mark, H&E 200x)

Figure 2

Section showing broad aseptate hyphae of mucor and thin septate hypahe and spores of aspergillosis. (H&E, 200x)

Figure 3

Gomoris silver methenamine stain showing (A). Hyphae of mucor and aspergillosis (B) Broad aseptate hyphae of mucormycosis (C & D) Fruting bodies and spores of aspergillosis.

Discussion

Diabetes is a well known predisposing factor for invasive fungal infections as it can alter the immunological response of patients to the infections. There is decreased granulocyte mediated phagocytosis in these patients. Also hyperglycemia provides a good microenvironment for fungal growth. Mucormycosis is a lethal opportunistic infection. The various generas responsible for infection are Rhizopus (most common), Rhizomucor and Absidia.1 The Fungal hyphae have a predilection for growth into arteries, lymphatics and nerves. These invades the vessels and cause occlusion of vessels by fibrin reaction leading to ischaemia and infarction. The black necrotic eschar produced due to infarction is characterstic of mucormycosis. Rhino-orbital-cerebral form of mucormycosis is the most common among gastrointestinal, pulmonary, subcutaneous, central nervous system, disseminated and other miscellaneous syndromes.4 The fungus can extend to orbit and brain along the vessels.3 The criteria for the clinical diagnosis of mucormycosis a given by Smith and Krichner5 are:

Invasive Aspergillosis produces yellowish or black necrotic material and most commonly affects patients with uncontrolled diabetes , leukemia and immunodeficiency.6

The differential diagnoses in such clinical setting include septic emboli, atherosclerotic vasculopathy, vasculitis, local streptococcal and clostridial infection, and invasive Aspergillosis.4

The diagnosis is based on histoptahological demonstration of fungal hyphae which can be further highlighted by special stains like PAS and GMS. A culture can further support the diagnosis although it is not mandatory.

An early diagnosis, prompt institution of antifungal therapy (amphotericin) with timely surgical debridement and correction of underlying predisposing factor is the key to survival in cases of invasive mycosis.1 Nephrotoxicity and other side effects of amphotericin is an obstacle to treatment for which less toxic forms of the drug ‘ such as liposomal amphotericin B, colloidal dispersion amphotericin B, and amphotericin B lipid complex ’ can be helpful.7

Conclusion

Although a very few cases of coexistence of mucormycosis and aspergillosis are reported in diabetic patient , a high suspicion should always be kept for timely diagnosis and early treatment of these cases.

Source of Funding

None.

Conflict of Interest

None.