Sebaceous cysts with unpleasant twists: cutaneous myiasis with Dermatobia hominis.

Dermatobia hominis (human Bot fly) causes furuncular myiasis (larval infection) in Central and South America. This report describes a case in a member of the UK Armed Forces who had recently taken part in an overseas training exercise in Belize. The importance of clinical history (including travel history) is highlighted. We also describe the outcomes of conservative treatment and surgical intervention for separate lesions in the same patient.

Assessing the burden of human cysticercosis in Vietnam.

OBJECTIVES: To describe the occurrence of cysticercosis in patients living in rural areas of Northern Vietnam presenting clinical signs of neurocysticercosis. METHODS: Serological antigen detection, reflecting current infection with viable larval stages of Taenia solium, was used to estimate the prevalence of active cysticercosis in this patient population. RESULTS: The seroprevalence in epileptic patient population was <10%. However, antigen detection cannot detect dead cysticerci, which may also cause clinical signs. Therefore, the seroprevalence figures shown here may underestimate the role of neurocysticercosis as a causal agent of epilepsy and headaches in this population. CONCLUSIONS: Human and porcine cysticercosis remain public and veterinary public health problems in Northern Vietnam and probably in other parts of the country.

[Subcutaneous dirofilariasis of the upper lip in Tunisia]. / Dirofilariose sous-cutanée en Tunisie : une observation à localisation labiale.

INTRODUCTION: Dirofilariasis is a rare anthroponotic disease caused by Dirofilaria, the principal reservoir of which is the dog. The first case of subcutaneous dirofilariasis in Tunisia was reported in 1990. CASE REPORT: We report a case involving a 40-year-old woman living in northeastern Tunisia who presented with a subcutaneous lesion of the upper lip resembling a sebaceous cyst. Excisional biopsy released a worm identified on morphologic examination as Dirofilaria repens. Only excision allows simultaneous diagnosis and treatment. CONCLUSION: This is the 14th case of dirofilariasis reported in Tunisia. This parasitic disease is probably underestimated in our country. It should be considered for all subcutaneous nodules, regardless of localisation.

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. RESULTS: Gross: seven thick-walled 'cysts' containing clear or straw-colored fluid were investigated. Histopathology: the pseudocysts contained a palisade of epithelioid histiocytes and giant cells. Focal periodic acid Schiff (PAS)-positive eosinophilic fragments, some resembling keratin 'flakes', were identified within the lumen or within the cellular palisade, consistent with a PGP reaction to fragmented E. granulosus membrane. Clinical correlation: the initial histopathological diagnosis of two patients was ruptured epidermoid cysts with an assumed granulomatous reaction to eosinophilic keratinous debris. Subsequent diagnosis of CE in the liver and cervical soft tissue necessitated review of the 'epidermoid cysts'; PAS-positive E. granulosus membranous fragments masqueraded as keratinous debris. Renal, hepatic and pleuropulmonary CE were confirmed in the remaining patients following confirmation of an echinococcal PGP reaction. CONCLUSION: Heightened awareness and obsessive appraisal of subcutaneous PGP reactions for subtle, focal, PAS-positive and echinococcal membranous fragments are pivotal to the diagnosis that also serves as a clue to visceral CE.

A sebaceous cyst with a difference: Dermatobia hominis.

Dermatobia hominis causes furuncular myiasis and is endemic to South America. This report describes a case in a young woman who had recently visited Belize, highlighting the importance of clinical history (including travel history) and close liaison between pathologist and surgeon.

Ultrastructure of in vivo-produced caryocysts containing the coccidian Caryospora bigenetica (Apicomplexa: Eimeriidae).

A cotton rat was inoculated orally with oocysts of Caryospora bigenetica from the feces of a rattlesnake. Sixteen days later the rat was euthanized, and portions of the scrotum, foot pad and muzzle were processed for histological sections and transmission electron microscopy. Sporozoites within caryocysts had typical coccidian features such as an anterior and posterior refractile body, centrally located nucleus, micronemes, rhoptries, a conoid, a micropore near the anterior refractile body, a posterior pore, amylopectin granules, lipid bodies, a Golgi-like body, a mitochondrion and subpellicular microtubules. The infected host cell was spherical and surrounded by a fibrous wall-like covering, 0.35-1.00 microns thick. This outer covering, when viewed in stained histological sections, was periodic acid-Schiff (PAS)-positive.