Pulmonary Mucormycosis (Zygomycosis) Presenting as an Infective Exacerbation of Chronic Obstructive Pulmonary Disease

Abstract

Mucormycosis is a life-threatening fungal infection whose incidence has been rising recently, mainly due to the increasing use of immunosuppressive and corticosteroid treatment. In previous decades, mucormycosis was associated with a very poor prognosis as mortality was approximately 100%. Mortality rates reported in recent literature have only slightly improved despite the availability of targeted therapy with amphotericin B. Pulmonary mucormycosis is characteristically encountered in severely immunocompromised hosts, while rhino-orbital disease is often seen in individuals with diabetes mellitus. We report a rare case of fulminant pulmonary mucormycosis as an exceptionally rare complication of corticosteroid treatment in a 76-year-old patient with chronic obstructive pulmonary disease (COPD) and diabetes. The patient had presented with typical symptoms of an infective COPD exacerbation. The interesting aspects of our case were the absence of malignancy or immunosuppression, the isolation of Rhizomucor species, and the fungal invasion of the pleura and pericardium. Unfortunately, our patient died on the 49th day of hospitalisation, despite appropriate treatment.

Learning points: Pulmonary mucormycosis in patients with known respiratory disease may mimic an exacerbation of their lung disease, thus delaying diagnosis.Pulmonary mucormycosis can complicate corticosteroid treatment in elderly individuals with other predisposing factors, which is an emerging clinical concern.Pulmonary mucormycosis remains a potentially fatal disease, although early diagnosis and appropriate medical and surgical management can improve outcomes.

Keywords: Mucormycosis; Rhizomucor; chronic obstructive pulmonary disease; diabetes mellitus; zygomycosis.

Figure 1

Admission chest x-ray (AP film) demonstrating consolidation in the left lower lobe and blunting of the left costophrenic angle

Figure 2

Subsequent chest x-ray (AP film) demonstrating multiple lung cavities, particularly in the left lower zone, and blunting of both costophrenic angles

Figure 3

A thorax CT scan demonstrating multiple cavity formation, particularly in the left lower lobe, and a left-sided pleural effusion

Figure 4

Mould growth on SDA 2% showing a cotton, candy-like colony that was velvety to floccose and, in time, became yellowish-brown in colour

Figure 5

Lactophenol cotton blue stain demonstrating long and hyaline hyphae, stolons, rhizoids and sporangiophores