A clinicopathologic study of skin appendageal tumors.

BACKGROUND: Appendageal skin tumors belong to a heterogenous group of tumors with specific histopathology. The aim of this study is to determine the pattern of appendageal tumors in skin biopsies done in our department. METHODS: This is a 3-year retrospective descriptive study of all patients who were diagnosed to have skin appendageal tumors in our department, and the diagnoses were confirmed by histopathology. The tumors were classified as eccrine, hair, sebaceous, and apocrine after a detailed examination of routine hematoxylin and eosin sections. RESULTS: The total number of cases in the study was 33-10 males and 23 females. Tumors with eccrine differentiation constituted the maximum, 17 cases (51.5%); followed by tumors with hair differentiation, 12 cases (36.36%); tumors with sebaceous differentiation, 2 cases (6.06%); and apocrine tumors, 2 cases (6.06%). Syringoma constituted the commonest eccrine tumor, 14 cases (42.42%); while trichoepithelioma was the commonest hair tumor, 9 cases (27.27%). The other eccrine tumors were eccrine spiradenoma, 2 cases (6.06%); and nodular hidradenoma, 1 (3.03%). The other hair tumors were pilar cyst, 2 (6.06%); and pilomatricoma, 1 (3.03%). The sebaceous tumors constituted 2 cases (6.06%) of nevus sebaceous. Syringocystadenoma papilliferum, 1 (3.03%); and cylindroma, 1 (3.03%), constituted the apocrine tumors. CONCLUSIONS: Appendageal skin tumors are relatively uncommon. Histopathology is mandatory for the diagnosis. No tumor showed malignant change in this study.

Analysing the performance of personal computers based on Intel microprocessors for sequence aligning bioinformatics applications.

Aligning specific sequences against a very large number of other sequences is a central aspect of bioinformatics. With the widespread availability of personal computers in biology laboratories, sequence alignment is now often performed locally. This makes it necessary to analyse the performance of personal computers for sequence aligning bioinformatics benchmarks. In this paper, we analyse the performance of a personal computer for the popular BLAST and FASTA sequence alignment suites. Results indicate that these benchmarks have a large number of recurring operations and use memory operations extensively. It seems that the performance can be improved with a bigger L1-cache.

Primary mucocutaneous histoplasmosis presents as oral ulcer .

We are reporting a rare case of primary mucocutaneous histoplasmosis. A 47-year-old male with a part-time job of rearing pigeons presented with a non-healing oral ulcer with no associated systemic symptoms. Differential diagnosis of oral ulcerative lichen planus, squamous cell carcinoma and mucocutaneous leishmaniasis was considered. Histopathology showed multiple organisms with a peripheral halo, stained strongly with Gomori methenamine silver stain.

Pseudoxanthoma elasticum with cerebrovascular accident.

A 65-year-old male presented with right hemiparesis and skin lesions. On examination, the patient had multiple, discrete, skin-colored papules on the neck and upper chest with wrinkling of the skin. The lateral part of the trunk and medial aspect of both upper arms showed atrophic plaques. A computerized tomography scan of the head showed dilatation of the basilar artery with a frontoparietal infarct. Funduscopic examination showed characteristic angioid streaks. Skin biopsy of the papule and atrophic plaques showed epidermal atrophy, calcium deposits in the mid-dermis and basophilic clumped and fragmented elastic fibers in the mid- and lower dermis, all findings consistent with pseudoxanthoma elasticum. We are reporting here a case of pseudoxanthoma elasticum with cerebrovascular accident.

A clinical and histopathological study of pityriasis lichenoides.

BACKGROUND: Pityriasis lichenoides is a papulosquamous disorder of unknown etiology with remissions and exacerbations. Histopathology helps greatly in the diagnosis of this condition. AIM: We studied clinical and histopathological features of pityriasis lichenoides in our patients. METHODS: This is a 3-year retrospective and prospective, descriptive study of all patients clinically diagnosed as pityriasis lichenoides and confirmed by histopathology. All patients were studied clinically and histopathologically. RESULTS: There were 51 (30 males and 21 females) cases of pityriasis lichenoides in the study period. The maximum number of cases, 14 (27.45%) were in their second decade of life. Pityriasis lichenoides chronica was diagnosed in 39 cases (76.47%) and pityriasis lichenoides et varioliformis acuta (PLEVA) in 12 cases (23.53%). Histopathologically, basal cell vacuolation and perivascular infiltrate were seen in all the cases. Exocytosis was seen in 45.1% of the cases. All the cases of PLEVA showed lymphocytic vasculitis albeit without fibrinoid deposition in the vessel walls. CONCLUSION: Pityriasis lichenoides is not a rare disorder, and is not a true lymphocytic vasculitis as blood vessel damage and fibrinoid deposition in the blood vessel walls were not seen in this study.

The "sign of groove", a new cutaneous sign of internal malignancy.

A 36-year-old young male with multiple heterosexual contacts presented with bilateral inguinal bubo and the classical "sign of groove". A diagnosis of lymphogranuloma venereum (LGV) was made and a three-week course of doxycycline was given. Lack of response prompted us to investigate further. A biopsy of the bubo was consistent with non-Hodgkin's lymphoma (NHL). Immunohistochemistry of the lymph node done at the Regional Cancer Center (RCC), Trivandrum, confirmed the diagnosis as NHL of diffuse large B-cell type. The second patient, a 32-year-old male with two unprotected heterosexual contacts presented with a left-sided inguinal bubo of six weeks duration. An empirical course of doxycycline was given even though investigations did not reveal any STI. Lack of response prompted us to do a lymph node biopsy, which was consistent with NHL, which later with immunohistochemistry was confirmed as NHL, diffuse large cell type. We are reporting here that the "sign of groove" is not specific for LGV as thought earlier, but can occur in NHL also.

A study of mortality in dermatology.

BACKGROUND AND AIMS: Certain dermatological conditions are life-threatening and can cause mortality. The aim of this study is to find out the dermatological diseases leading to death in our indoor patients. METHODS: A record-based retrospective descriptive study of dermatology cases who died during the period of 1995 to 2001. RESULTS: The total number of cases analyzed was thirty-seven. There were 24 males and 13 females. The maximum number of deaths occurred in the age group 61-70. Vesiculobullous disorders were the commonest cause of death, found in 18 cases (48.6%), followed by drug reactions in 5 (13.5%), malignancies in 5 (13.5%) and collagen vascular disease in 2 cases ((5.40%). Pemphigus was the commonest fatal vesiculobullous disorder (13 cases - 35.13%), and toxic epidermal necrolysis the commonest drug reaction (3 cases - 8.10%). CONCLUSION: Area of skin involvement, electrolyte imbalance and septicemia were important factors leading to death in pemphigus and toxic epidermal necrolysis. We advocate that such patients should be managed in burns unit or ICU units.

Malignant acanthosis nigricans with liver secondaries from an occult primary adenocarcinoma of gastrointestinal tract.

A 38-year-old female presented with hyperpigmented velvety plaques on the nape and the sides of the neck with diffuse pigmentation of the face and flexures suggestive of acanthosis nigricans. The dorsa of both the hands showed increased rugosity, hyperpigmentation and hyperkeratosis of the palms, suggestive of tripe palms. Investigations revealed multiple secondaries in the liver. Histopathology showed the secondaries to be from adenocarcinoma of the gastrointestinal tract.

Chronic granulomatous disease.

A 2(1/2)-year-old child presented with multiple discrete granulomatous lesions on the face and flexural regions since the age of 2 months along with lymphadenopathy. The patient also had recurrent bouts of pyodermas and respiratory tract infections. Biopsy of the lesion showed necrosis of tissue with suppuration and histiocytes but no evidence of tuberculosis, fungal infections or atypical mycobacteria. Lymph node biopsy also showed necrosis with suppuration but no infective organism. Nitroblue tetrazolium test was negative indicating that the neutrophils failed to oxidize the dye. We are reporting here a rare case of chronic granulomatous disease.