Cytokeratin expression in gastrointestinal stromal tumors: morphology, meaning, and mimicry.

Background: Gastrointestinal stromal tumors (GISTs) are biologically distinctive neoplasms harboring KIT and PDGFRA mutations. Cytokeratin expression in GISTs is an under-recognized diagnostic pitfall, especially in high grade GISTs with limited biopsy material and from metastatic sites.

Materials And Methods: We evaluated the histomorphology and expression of four 'broad-spectrum' cytokeratin markers, AE1-AE3, CAM 5.

Pediatric plasmablastic lymphoma: a clinicopathologic study.

Plasmablastic lymphoma (PBL) is reported rarely in children. To date, 10 cases are documented in the English-language literature. This study, based on 13 biopsies from 11 HIV-positive children (9 males, 2 females), documents the clinicopathologic features of PBL.

Infantile donovanosis presenting as external auditory canal polyps: a diagnostic trap.

Two infants, 6 months and 4 months of age, presented with bilateral or unilateral external auditory canal polyps and otorrhea, respectively. Additional findings on examination included otitis media and mastoiditis. Tympanic membrane perforation was noted in one patient and a postauricular abscess in the other.

Bartonella quintana-induced vulval bacillary angiomatosis.

Bacillary angiomatosis (BA) is an increasingly reported infection, mainly in patients with acquired immunodeficiency syndrome. Different epidemiological risk factors are associated with the transmission of the causative agents, Bartonella henselae and B. quintana.

The spectrum of HIV-related nephropathy in children.

Background: Despite the burden of human immunodeficiency virus (HIV) disease in Southern Africa, there have been few reports of HIV-related nephropathy in children. This study outlines the spectrum of HIV-1-related kidney diseases of children in KwaZulu-Natal, South Africa.

Methods: A review of the clinical presentation, laboratory and histopathological findings of children diagnosed with HIV-related nephropathy.

Extra-uterine myoid tumours in patients with acquired immunodeficiency syndrome: a clinicopathological reappraisal.

Aims: AIDS-associated myoid tumours (AIDS-MTs), often Epstein-Barr virus (EBV)-associated (EBV-positive MTs), include smooth muscle tumors (SMTs) and the relatively recently recognized myopericytomas (MPCTs). The myoid immunophenotype of AIDS-MTs has been documented inconsistently. The aim of this study was to reappraise the phenotypic and immunophenotypic features of extra-uterine AIDS-MTs and the clinical profile of afflicted patients.

Langerhans cells in anaplastic Kaposi sarcoma with a paucivascular phenotype: a potential diagnostic pitfall.

Anaplastic Kaposi sarcoma (AKS), a rare variant of Kaposi sarcoma, has a poorly recognized histomorphologic spectrum, including a paucivascular phenotype, that mimics a range of undifferentiated malignancies. This study, that highlights the hitherto undocumented phenomenon of S100-protein-positive Langerhans cells (SLCs) as a potential diagnostic pitfall in paucivascular AKS, involved review of nine such AKS that required diagnostic immunohistochemical (IHC) work-up. All biopsies had a predominant or exclusive spindle or epithelioid cell infiltrate.

Periampullary Epstein-Barr virus-associated myopericytoma.

Although myopericytoma occurs predominantly in the extremities, a wider anatomical distribution, malignant variant, and association with Epstein-Barr virus have been recognized recently. However, benign, malignant, or Epstein-Barr virus-myopericytoma has not been documented in the gastrointestinal tract to date. We report a periampullary Epstein-Barr virus-myopericytoma in a patient with AIDS who presented with obstructive jaundice.

Dermal Epstein Barr virus--associated leiomyosarcoma: tocsin of acquired immunodeficiency syndrome in two children.

Although rare in childhood, a relatively high incidence of smooth muscle tumors are recognized in patients with AIDS, mainly in association with Epstein Barr virus (EBV) infection. Although EBV-associated smooth muscle tumors have been documented rarely in the subcutis of AIDS patients, dermal involvement has not been described to date. This report describes dermal EBV-associated leiomyosarcomas (EBV-LMS) with a nodular but superficial plaque-like appearance on the lower limbs of 2 males, 9 and 12 years old.

Cutaneous colesional acquired immunodeficiency syndrome associated Kaposi sarcoma and cryptococcosis.

The clinicopathologic features of 4 AIDS patients with cutaneous colesional Kaposi sarcoma (KS) and cryptococcosis, a rare phenomenon, are described. Biopsies from 3 patients who were highly active antiretroviral therapy (HAART)-naive demonstrated predominant KS with a conspicuous spindle cell component and small aggregates of cryptococcal yeasts in 2 biopsies and predominant gelatinous cryptococcosis with attenuated KS spindle cells in 1 biopsy. One patient was HAART exposed.

Gastric plexiform angiomyxoid myofibroblastic tumor.

Plexiform angiomyxoid myofibroblastic tumor (PAMT) is a relatively recently described gastric tumor with a peculiar plexiform growth pattern. PAMT is typified by a myofibroblastic immunophenotype that distinguishes it from the more common gastrointestinal stromal tumors and the rarely documented fibromyxomas. We report an additional PAMT, the seventh tumor with this label, which was an incidental finding on abdominal computed tomography scan of a 35-year-old Indian female.

Pediatric renal cryptococcosis: novel manifestations in the acquired immunodeficiency syndrome era.

Pediatric cryptococcosis has been documented in various organs, but pediatric renal cryptococcosis (RC) remains undocumented to date. The authors report RC in 2 children with AIDS, 7 and 9 years of age, with proteinuria. Both patients, on antiretroviral therapy (ARV) for 28 (patient 1) and 54 (patient 2) weeks each, had secured viral immunosuppression, but immune restoration was realized by patient 1 only.

Paediatric intussusception caused by acquired immunodeficiency syndrome-associated Kaposi sarcoma.

Purpose: To document the clinicopathological features of paediatric intussusception caused by acquired immunodeficiency syndrome (AIDS)-associated Kaposi sarcoma (KS).

Methods: Clinicopathological features of six patients with AIDS-KS-associated intussusception were obtained retrospectively from departmental and hospital records.

Results: Six debilitated male children, without cutaneous KS, were presented with abdominal pain and vomiting for >1 week.

Granulomas in acquired immunodeficiency syndrome-associated cutaneous Kaposi sarcoma: evidence for a role for Mycobacterium tuberculosis.

Background: Co-lesional acquired immunodeficiency syndrome-associated cutaneous Kaposi sarcoma (AIDS-KS) and Mycobacterium tuberculosis-associated granulomatous inflammation are undocumented.

Method: Retrospective appraisal of skin biopsies with co-lesional AIDS-KS and microscopic tuberculosis (TB).

Results: Sixteen biopsies from nine males and seven females form the study cohort.

Extra-anogenital bilharziasis cutanea tarda revisited.

Background: Even in schistosomiasis-endemic areas, extra-anogenital bilharziasis cutanea tarda (E-BCT) is rare. To date, the occurrence of E-BCT in pre-existing cutaneous pathology is undocumented. The study was undertaken to document the expanded clinicopathological spectrum and to comment on the putative pathogenetic mechanisms of a Schistosoma hematobium-associated E-BCT.

Subcutaneous palisading granulomatous pseudocysts of Echinococcus granulosus origin.

Background: Palisading granulomatous reactions are documented in many diseases. Although subcutaneous cystic echinococcosis (CE) is documented rarely, a subcutaneous palisading, granulomatous, pseudocystic (PGP) reaction to elusive Echinococcus granulosus membranous components, in the absence of cutaneous fistulization, is undocumented.

Methods: Seven-year clinicopathological review of subcutaneous echinococcal PGP reactions.

Molluscum-like cutaneous cryptococcosis: a histopathological and pathogenetic appraisal.

Background: Molluscum-like cutaneous cryptococcosis (MLCC) is characterized by hypopigmented or skin-colored papules with central umbilication. The histomorphological nuances of Cryptococcus neoformans infection that effect mimicry of molluscum contagiosum are undocumented. This histopathological study was undertaken to assess the histopathological characteristics of MLCC and to determine potential evolutionary pathogenetic mechanisms and significance.

Otic pneumocystosis in acquired immune deficiency syndrome.

AIDS-associated otic pneumocystosis is rare. Of 14 cases documented mainly as case reports up to now, only 1 has been reported in the surgical pathology literature. We report 6 males, mean age of 32.

Cryptococcosis masquerading as a tuboovarian abscess.

This report describes a 25-year-old human immunodeficiency virus- seropositive patient who initially presented with clinical features of a tuboovarian abscess. After a poor response to antibiotic therapy, laparotomy and excision of a right-sided, unilocular, pseudocystic ovarian mass measuring 140 x 80 x 60 mm were undertaken. Mucoid gelatinous material, with a glistening appearance and slimy consistency, coated the inner surface of the thick wall.

Cryptococcal inflammatory pseudotumors.

"Inflammatory pseudotumors" (IPTs) embrace a heterogeneous spectrum of reactive, infective, and neoplastic entities, that are characterized by a clinical mass composed of a histologic proliferation of spindle cells in a background of inflammatory cells and collagen fibers. Although a spectrum of microorganisms have been identified in infective IPTs, mycobacterial infective IPTs are reported most commonly. We document 5 solitary cryptococcal IPTs, in 2 males and 3 females, aged 19 to 43 years, in the soft tissues of the anterior chest wall, thigh, and arm.