DOI: 10.36347/sasjm.2023.v09i06.002

Pages: 583-586

The alopecic aseptic nodule of the scalp (NAAS) is a recently described entity known as a "pseudocyst of the scalp". It can be confused with dissecting folliculitis of the scalp (Hoffmann's disease) by certain clinical signs. We report three cases of NAAS mimicking MH with favourable evolution under doxycycline associated with intra-lesional corticotherapy. Case 1: A 36-year-old man presented with painful nodules of the scalp. Examination revealed two fluctuating subcutaneous nodules measuring 4 and 5 cm, both painful. The skin opposite the nodules was alopecic and not scarred. Case 2: A 28-year-old man presented with a scalp nodule that had been present for 3 months. Clinical examination revealed a fluctuating, painful subcutaneous nodule measuring 7cm, alopecic and non-scarring, with surrounding small patches of alopecia. In addition, inflammatory acne lesions were noted on the face. Case 3: A 33-year-old obese male smoker presented with a scalp nodule. Examination revealed a painful subcutaneous nodule measuring 3 cm, with smooth alopecic skin. Discussion: The pathophysiology of NAAS remains poorly understood, and a link with the spectrum of follicular occlusion pathologies has been suggested. Inflammatory acne was observed in two of our patients. The biopsy was non-specific; the pus came back sterile in all cases; after aspiration, the patients benefited from intra-lesional corticosteroid therapy associated with doxycycline 100mg/dr with a good evolution. Conclusion: Aseptic alopecic nodules of the scalp are clinically similar to folliculitis dissecans of the scalp. Certain clinical signs can help the practitioner to make the correct diagnosis in order to avoid aggressive treatment.