Histopathological changes in the arrector pili muscle of normal appearing skin in leprosy patients.

BACKGROUND: Leprosy is a chronic inflammatory disease caused by Mycobacterium leprae, which affects not only the peripheral nerves and skin, but also various internal viscera through hematogenous spread, especially in lepromatous cases. Histology in its own way plays a vital role, not only in classifying the established lesion, but also in confirming the clinical diagnosis. During the latent period of subclinical involvement, the apparently normal looking skin might also be undergoing some pathological changes. METHODS: We investigated skin biopsy material taken from 60 patients with clinically diagnosed leprosy at Subharti Hospital, Subharti Medical College, Meerut, India. Hematoxylin and eosin staining and Harada's modified allochrome method for acid-fast bacilli were applied for histological investigations. RESULTS: The pattern of leprosy among the patients was indeterminate in 25 cases (41.7%), tuberculoid in 14 (23.3%), borderline tuberculoid in six (10%), borderline leprosy in four (6.7%), borderline lepromatous in four (6.7%), and lepromatous leprosy in seven (11.7%). Changes were seen in the arrector pili muscle of normal appearing skin in all types of leprosy, but involvement was greater at the lepromatous end of the spectrum compared to the tuberculoid end. CONCLUSIONS: Results of this study revealed definitive histological changes in the arrector pili muscle in normal appearing skin. The presence of AFB is significant as far as dissemination and transmission of the disease is concerned.

Circumferential skin folds in a child: a case of Michelin tire baby syndrome.

A six-month-old girl who presented with dermatitis was found to have multiple, symmetric, deep, gyrate skin folds involving her trunk and similar circumferential lesions on her extremities since birth. She had a characteristic round face with hypertelorism, depressed nasal bridge, thin, down-turned vermillion border of upper lip and short neck. Skin biopsy demonstrated increased smooth muscle fibers in the deeper dermis. A diagnosis of Michelin tire baby syndrome was made. Clinical features, histopathology, differential diagnosis and prognosis of this rare disorder have been discussed.

Acquired smooth muscle hamartoma.

Smooth muscle hamartoma is an uncommon, usually congenital, cutaneous hyperplasia of the arrectores pilorum muscles. When it is acquired, it may be confused with Becker's nevus. We report a case of this rare tumor in a 19-year-old man. The disease started several years ago as multiple small skin-colored papules that subsequently coalesced to form a large soft plaque on the back of the left shoulder. The diagnosis of acquired smooth muscle hamartoma was confirmed on histopathology. The patient was reassured about the benign nature of the lesion and was not advised any treatment.

A study of scrotal biopsy in subsided cases of lepromatous leprosy.

Scrotal biopsies were obtained from 38 cases of lepromatous leprosy who were clinically subsided and had negative skin smears. Twenty six (68.4%) of these cases revealed bacilli in the dartos muscle. None except one showed a specific lesion in the dartos. Bacilli obtained from 2 out of 7 cases multiplied in the mouse foot-pad. Bacilli were found to be persisting in the dartos muscle despite prolonged treatment before as well as after clinical subsidence of the disease. The persisting bacilli in this situation could be a cause of relapses.