Cocaine-induced plasma cell orificial dermatomucositis

A woman in her 40s presented to our clinic with a three-month history of progressively enlarging and painful facial plaques that had failed to respond to oral terbinafine, previously prescribed in the presumed setting of a superficial fungal infection. The patient reported no systemic symptoms such as fever, malaise, weight loss or joint pain. Physical examination revealed a well-demarcated, exudative plaque measuring approximately 4 cm × 2 cm involving the supralabial region, nasal vestibule and distal nasal tip. No oral or ocular mucosal involvement was observed, and there were no additional skin lesions or lymphadenopathy. When specifically asked, the patient admitted to recent intranasal cocaine use, an important detail not disclosed during the initial consultation. Laboratory tests revealed neutrophilic leukocytosis with mild eosinophilia and elevated cytoplasmic antineutrophil cytoplasmic antibody (C-ANCA) titers. Urine toxicology confirmed the presence of cocaine. An otolaryngological examination revealed no septal perforation or internal nasal ulceration. Histopathological examination of a skin biopsy from the lesion showed a dense dermal inflammatory infiltrate with a predominant lymphoplasmacytic pattern, a markedly increased number of IgG4-positive plasma cells (with an IgG4/IgG ratio greater than 40%), and areas of storiform fibrosis. No fungal elements were identified using specific stains. Based on the clinical presentation, laboratory findings and histopathology, a diagnosis of cocaine-induced dermatomucositis (CID) was made. The patient was enrolled in a drug detoxification program and started on oral prednisone at a dose of 45 mg/day, which was gradually tapered. The lesion resolved completely within two months and no recurrence has been observed to date (Fig. 1).

Figure 1.

Clinical presentation and histopathological findings. (A and B) Exudative plaque measuring 4 cm × 2 cm involving the supralabial region, nostrils and inferior pole of the nose. (C–E) Biopsy showed a dense inflammatory infiltrate in the dermis, principally lymphoplasmacytic, with a predominance of plasma cells and an increased IgG4/IgG ratio (>40%), as well as storiform fibrosis (C, H&E stain, 4×; D, H&E stain, 20×; E, Ig and IgG4 stain, 2× and 40×).

CID is a rare but increasingly recognized inflammatory condition characterized by periorificial skin involvement, elevated serum and tissue IgG4 levels and a strong association with intranasal cocaine use, often adulterated with levamisole. It may closely mimic infectious or autoimmune diseases, particularly those affecting the nasolabial area. In primary care, early detection is essential.¹ Primary care physicians have a central role in identifying this condition, particularly in patients presenting with persistent or atypical facial lesions that do not respond to standard therapies. A detailed social history, including substance use, combined with appropriate serological testing and dermatological referral for biopsy can significantly improve diagnostic accuracy. The differential diagnosis should also include autoimmune conditions such as granulomatosis with polyangiitis or discoid lupus erythematosus, as well as chronic infections and neoplastic processes affecting the nasolabial region.^2–4 The presence of increased IgG4-positive plasma cells suggests a potential immunological mechanism that remains to be fully elucidated but may be a distinctive histopathological marker for this entity. Although IgG4-related disease was not suspected clinically, the presence of abundant IgG4+ plasma cells raises the possibility of overlapping immunopathological mechanisms, and highlights the potential value of this finding in distinguishing CID from other inflammatory or autoimmune dermatoses.^2,5 Early cessation of cocaine use is essential, as continued exposure may exacerbate or perpetuate the disease.^1,2 Timely diagnosis and initiation of systemic corticosteroids may result in complete clinical remission and prevent progression or recurrence. Most importantly, this case underscores the critical role of thorough social history-taking in patients with atypical facial lesions unresponsive to conventional therapy.

CRediT authorship contribution statement

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  Miguel Mansilla-Polo and Francisco Reyes-Albaladejo managed clinical treatment and procedures, contributing to the development of this paper.

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  Rafael Botella-Estrada supervised the work.

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  All authors had access to the data and played a role in writing this manuscript.

Informed consent

Oral and written consent was obtained to publish this image.

Ethical approval

The procedures followed here were in accordance with the ethical standards of the responsible committee on human experimentation and with the Helsinki Declaration of 1975, as revised in 1983. We have not use patients’ names, initials, or hospital numbers.

Funding

This article has no funding source.

Conflicts of interest

The authors have declared no conflicts of interest.