CPC08: A case of cutaneous malakoplakia: a pain in the neck

F. Po-Chao Chiu,¹ K. Hajkowicz,² T. Taheri,^3,4 D. McCrystal⁵ and K. Rodins⁶

¹Dermatology, Princess Alexandra Hospital; ²Infectious Disease, Royal Brisbane and Women's Hospital; ³School of Medicine, University of Queensland; ⁴Anatomical Pathology, Pathology Queensland; ⁵Otolaryngology, Royal Brisbane and Women's Hospital; and ⁶Northern Dermatology, Brisbane, Australia

Malakoplakia is an uncommon, granulomatous inflammatory disorder that typically occurs within the genitourinary tract. Cutaneous malakoplakia is uncommon and mainly occurs in the perianal and genital areas; skin involvement elsewhere is rare. Clinically, skin lesions present as persistent papules and nodules, which are sometimes ulcerated; they are skin-coloured, yellow or pink. Histologically, foamy histiocytes (von Hansemann cells) with basophilic inclusions (Michaelis–Gutmann bodies) are demonstrated. The precise aetiology is unknown but may reflect the result of insufficient killing of bacteria by macrophages. We report the case of an immunocompetent 92-year-old white man who developed a painful, rapidly enlarging nodule on the right side of his neck with associated discharge and ulceration. Malignancy was suspected, particularly as a positron emission tomography scan revealed additional inflammatory foci on the base of his tongue. Fine-needle aspiration of the neck lesion did not identify malignant cells. Rather, histology revealed intracytoplasmic von Kossa-positive, targetoid basophilic inclusion bodies within macrophages, consistent with malakoplakia. Tissue cultures grew Escherichia coli sensitive to amoxicillin–clavulanic acid. Debridement of the skin and oral sites followed by an 8-month course of antibiotics failed to clear the lesions. Changing the antibiotic to ciprofloxacin led to sustained improvement. Reviewing the literature, 78 cases of malakoplakia involving the head and neck have been reported. Of these, 27% were cutaneous and 14% occurred in the tongue. Other cases have involved the brain (15%), middle ear (8%), nasopharynx/nasal sinuses (6%), thyroid (5%), tonsils (5%), epiglottis/vallecula (5%), gums (4%), larynx (4%), salivary glands (3%), conjunctiva (3%) and cervical nodes (1%). Approximately half the patients (54%) had chronic illnesses or were immunocompromised. Unlike genitourinary tract malakoplakia, head and neck malakoplakia occurs more commonly in males than females (1·3 : 1). Antibiotics were used in 19% of cases, and had a cure rate of 58%. Fluoroquinolones were the most prescribed class of antibiotic (either alone or combined with other antibiotics) and resolved malakoplakia in 92% of cases. Twenty-seven per cent of cases were managed surgically, with a cure rate of 75%. A combination of surgery and antibiotic therapy has been used in 27% of cases, yielding the highest cure rate (84%). Malakoplakia should be considered in the differential of enlarging head and neck masses; histology is essential for diagnosis, owing to overlapping features with malignancy. When considering antibiotics, ciprofloxacin may be preferable to amoxicillin/clavulanic acid, depending on culture sensitivities. Finally, combining surgical management with antibiotic therapy may be more effective than either modality alone.