Role of direct immunofluorescence in dermatological disorders.

BACKGROUND: Direct immunofluorescence (DIF) test for tissue-bound autoantibodies, has been found to be of value in the diagnosis of several dermatological disorders. The location and pattern of deposition of immunoreactants helps in classifying various immune-mediated diseases. AIMS AND OBJECTIVES: The aim of this study was to analyze the concordance between the clinical, histopathological and DIF diagnosis in bullous and nonbullous lesions of the skin, and thus determine the impact of immunofluorescence on diagnosis. MATERIALS AND METHODS: A total of 215 skin biopsies performed in suspected immune-mediated vesiculobullous disease, vasculitis or dermatosis, were studied. Histopathological examination was done along with DIF study for deposits of immunoglobulin G(IgG), IgA, IgM, and C3. RESULTS: Direct immunofluorescence was positive in 103/215 cases. There was very good concordance between the clinical, histological and DIF results (observed agreement = 93.4%, κ =0.90, with 95% confidence interval = 0.86-0.94). The overall sensitivity of DIF in immune-mediated skin disorders was 98.0%. DIF was positive in 52/53 cases (98.1%) in the pemphigus group and 24/25 (96.0%) bullous pemphigoid cases. None of the clinically suspected cases of dermatitis herpetiformis showed DIF positivity. A positive lupus band test was seen in 9/9 (100%) cases of lupus erythematosus. DIF was positive in 10/10 (100%) clinically suspected cases of Henoch-Schönlein purpura. In 110 cases, negative DIF results helped to rule out immune-mediated vesiculobullous disorders, lupus erythematosus and vasculitis, and the final diagnosis was made on the basis of the clinical features and/or histopathology. CONCLUSION: Direct immunofluorescence is a useful supplement for the accurate diagnosis of immune-mediated dermatological disorders, and helps to classify various autoimmune bullous disorders. When the clinical features/histopathology are inconclusive, the diagnosis often can be made on the basis of the DIF findings alone. A combination of the clinical features, histopathology and DIF usually gives the best results.

An unusual presentation of primary cutaneous nocardiosis at a rare site: succesful treatment with a modified Welsh regimen.

INTRODUCTION: Primary cutaneous nocardiosis can present in various forms. Clinically, it can present as acute infection (abscess or cellulitis), mycetoma, or sporotrichoid infection. Mycetoma over the back is rare. CASE REPORT: We herein describe a case of primary cutaneous nocardiosis presenting as a mycetoma, caused by Nocardia brasiliensis. The patient had extensive lesions over the back, which can be attributed to the fact that the patient, being an agriculturist, has been exposed to recurrent trauma while carrying firewood and soiled sacks. He responded well to a modified Welsh regimen. Initially, within 2 cycles, the patient showed dramatic improvement clinically, wherein the sinuses, granulation tissue, and induration were no longer apparent. However, the patient showed a small discharging sinus at the end of 3rd pulse, so a total of 6 cycles were given. An additional 2 months of maintenance phase treatment with cotrimoxazole and rifampicin were given. On follow-up, the patient showed no recurrence at 6 months. CONCLUSION: We report a case of primary cutaneous nocardiosis presenting as a mycetoma on the back. Enlisting the help of a microbiologist allowed us to isolate the causative organism. Early recognition and prompt treatment prevents unwarranted surgical debridement and complications.

Unusual manifestations of Reiter's disease in a child.

Reiter's disease in a child, manifesting as circumscribed, thick, hyperkeratotic, rupioid lesions over the skin and later in the course of the disease developing pyopericardium and cardiac failure, is reported. Recovery of Chlamydia from the urethral discharge, too, was significant.

Chancroid or chancroidal ulcers.

1532 cases with genital ulcers were investigated, of whom 610 presented with features suggestive of chancroid; classic, multiple lesions of chancroid were observed in 312, while its other variants, i.e. dwarf, giant and phagedaenic chancroid were also seen. In addition, 162 cases had a conspicuous morphology characterised by a single ulcer which was well-defined, soft, tender, non-indurated and had weakening edges. These were termed chancroidal ulcers. The latter had a longer incubation period of 8-11 days. Absence of lymphadenopathy was prominent in these cases. The male/female ratio was 27/1. Persons of low socio-economic status in the sexually vulnerable age-group were predominantly affected. The prepuce, coronal sulcus and glans penis were the common sites of affliction in males, while the labia minora was frequently involved in females. Due to the limited value of gram-stained smears for the detection of H. ducreyi and lack of good culture media, chancroid and chancroidal ulcers should be differentiated clinically.