| Langerhans cell histiocytosis (LCH) is a rare clonal disease of the monocyte-macrophage system characterized by uncontrolled proliferation and accumulation of CD1a+ dendritic cells in various organs as a result of continuous immune stimulation. While LCH can present with a wide range of clinical manifestations, nail involvement is rare. To our knowledge, 22 cases have been documented in the literature till date and indicates poor prognosis and multisystem involvement. A 2-year-old male c/o swelling of distal digits and loss of nail plates on both hands and feet since 7 months. H/o intermittent fever, breathlessness, failure to thrive and was treated multiple times for pneumonia with temporary relief. Previously treated as suspected nail psoriasis and onychomycosis without improvement. Systemic examination: tachypnea, hepatomegaly. Cutaneous findings: erythematous bulbous swelling of nail bed of all fingers with thick, adherent haemorrhagic & honey coloured crusting associated with onycholysis. Multiple, discrete, skin coloured to hypopigmented papules on dorsam of B/L hands and trunk. Hemogram: anemia, leukocytosis, thrombocytosis, elevated ESR and ALP, TSH= 90. Chest X- ray: right sided pneumothorax with cavitations and patchy areas of fibrotic changes Skin biopsy from papule: moderately dense lichenoid infiltrate of histiocytes with slight epidermal hyperplasia. Large histiocytes with abundant amphophilic cytoplasm and large bilobed kidney shaped nuclei. Immunohistochemistry: CD1a and S100 positive. FDG-PET CT scan: proliferative disease affecting the skin, thyroid, liver, bone and lungs. V600E mutation of the BRAF oncogene: negative. Final diagnosis: Multisystem LCH with Twenty Nail involvement High-risk LCH protocol was started with weekly IV Vinblastine, daily oral Prednisolone and Etoposide. After developing fungal pneumonia, he was started on immunotherapy, oral Trametinib with complete improvement in 6 months post immunotherapy. Nail involvement though rare, can serve as a subtle clinical indicator of systemic disease and warrants evaluation to ensure timely diagnosis and management. |
