Mucormycosis presenting with dental pain and palatal ulcer in a patient with chronic myelomonocytic leukaemia: case report and literature review

Introduction: Mucormycosis is a rare fungal infection, with high morbidity and mortality. Palatal ulceration may suggest a number of differential diagnoses, one of which is rhinocerebral/craniofacial mucormycosis and for which it may be the first presenting clinical finding. We report a case of sinus mucormycosis in a patient with chronic myelomonocytic leukaemia‐2 (CMML‐2), now classified in the myelodysplastic/myeloproliferative neoplasms, presenting with dental pain and palatal ulcer. Case presentation: A 72‐year‐old female with CMML‐2 presented with pain of the left maxillary molar and a dark‐brown necrotic ulcer with a white irregular border on the hard palate. Invasive fungal infection was included in the differential diagnosis. Computerized tomography disclosed inflammatory lesions in the left nasal, ethmoid and frontal sinuses. Histological examination of the ulcer showed fungal hyphae typical of agents of mucormycosis. Rhizopus arrhizus was isolated from the culture. Liposomal amphotericin B was introduced, combined with haematological support and maxillectomy. Mucormycosis was controlled, but the patient died of progressive acute myeloid leukaemia and multiple bacteraemias. A literature review of rhinocerebral mucormycosis with palatal involvement disclosed 109 cases; palatal involvement was present among other presenting signs in 34 patients and as the presenting sign leading to diagnosis in nine cases, including the present case. Six of the nine patients (66.6 %) survived the infection, compared with 43 of 101 (42.6 %) with other signs at presentation. Conclusion: Palatal ulcer may represent an early sign of sinus mucormycosis. Awareness by healthcare professionals is critical for the prompt diagnosis of this rapidly developing and life‐threatening infection.