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Caught on Colonoscopy: Schistosomiasis Manifesting as a Single Colonic Polyp

A screening colonoscopy identified an unexpected diagnosis in a 64-year-old male patient. He was an asymptomatic landscaper who presented for a first-time screening colonoscopy based on age. His only active medical issue was psoriasis, for which he took apremilast. At the time of colonoscopy, he denied any bright red blood per rectum, melena, changes in […]

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Black flies, also known as buffalo gnats or turkey gnats, are blood-feeding insects in the insect family simuliidae. Immature black flies breed in fast-flowing water, from which the adults emerge in great swarms (usually) in spring or early summer. Black flies are notorious nuisance pests in certain parts of the world and are vectors of the agent of onchocerciasis in tropical areas. Nuisance biting alone can be serious, even fatal, with many reports of livestock and poultry deaths due to black fly biting.1, 2, 3 Outbreaks were a major problem in the southern United States during the early 20th century1 but disappeared until recently. This reemergence may be due to the elimination of harsh pesticides and the cleaning up of creeks and rivers.

Black fly bite reactions include papules, erythematous wheals, indurations, or extensive swelling of the affected area.4 In addition, adenopathy (black fly stiff neck) may occur from bites on the face, neck, and scalp.2 There are many reports of reactions to black fly biting in the northern United States and other parts of the world,2,5, 6, 7 but none from the southern United States, where black flies have typically not been a problem. Here we carefully document the timeline of bites and subsequent development of cutaneous lesions in an entomologist who was investigating a black fly outbreak along the Pearl River in central Mississippi during the spring of 2018.

Methods
The entomologist bitten by black flies was examined by the second author and bite reactions were described and photographed over the following 72 hours. Samples of the offending insect were collected and identified as Simuliim meridionale.

Results
From March 26 to April 2, at least 10 black fly bites were noted on the patient's arms, neck, and face. Bite reactions sometimes developed into large indurations by 48 hours (Figure 1). Two bites on the neck were carefully followed for 48 hours (Figure 2). At first, there was nothing but erythema and a small hemorrhagic center. Four hours later, lesions developed into a central wheal with surrounding erythema. The diagnosis was papular urticaria, presumably resulting from hypersensitivity to black fly salivary proteins. A raised urticarial papule developed at each bite site with surrounding erythema that itched intensely. Over the course of 24 hours, the urticarial lesions resolved, leaving only an erythematous flattened lesion. By 48 hours, the lesions had completely faded.

Development and Resolution of Cutaneous Lesions Caused by Black Fly Bites (Diptera: Simuliidae)

Black flies, also known as buffalo gnats or turkey gnats, are blood-feeding insects in the insect family simuliidae. Immature black flies breed in fast-flowing water, from which the adults emerge in great swarms (usually) in spring or early summer. Black flies are notorious nuisance pests in certain parts of the world and are vectors of […]

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Strongyloides stercoralis larvae on bronchoalveolar lavage.

Strongyloides Hyperinfection

A 37-year-old male from Honduras with a history of brainstem glioblastoma treated with radiation, bevacizumab, temozolomide, and dexamethasone presented with sudden onset of dyspnea, pleuritic chest pain, and hoarseness. He also complained of a pruritic abdominal rash and painful swallowing. Physical examination revealed a temperature of 36.9°C; expiratory wheezing; and maculopapular rash on the chest, […]

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T2-weighted magnetic resonance imaging was carried out. (A) Hyperintensities were noted in the bilateral thalami (arrows with black outline) and globus pallidi (arrows with red outline). (B) The white arrows indicate hyperintensities in the substantia nigra.

Brought Down by a Mosquito? West Nile Virus Encephalitis

  Neurologic symptoms in a previously healthy man spurred a battery of tests to determine the cause. The 51-year-old patient lived alone and was transferred to our intensive care unit from another facility. Emergency medical services personnel first brought him to his local emergency department, where he stated that he had not been feeling well […]

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(A) Ultrasonography demonstrated a linear hypoechoic structure (arrows) in an area of tissue breakdown in the left lobe of the liver. (B) Magnetic resonance imaging (MRI) showed a hypointense, coiled structure (arrows) in an abscess in the liver's left lobe. (C) MRI disclosed a linear hypointense structure—a worm, which is denoted by the arrow—in the abscess in the liver parenchyma. (D) MRI with contrast identified the liver abscess (asterisk) and the nonenhancing, hypointense worm (arrow).

A Worm Hole: Liver Abscess in Ascariasis

A patient with an infection that is often asymptomatic developed an uncommon complication. The 60-year-old woman presented with fever and pain in the epigastrium and right hypochondrium, symptoms that had existed for the previous 5 days. On touch, she was clearly febrile. Her temperature was 38.6°C (101.5°F). Her blood pressure and pulse rate were within […]

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bed bug

Bullous Reactions to Bedbugs

Bed bug bite reactions have been considered to be of minor medical significance. However, the findings presented in this study demonstrate that the not uncommon bullous reactions to bed bug bites reflect the presence of a local, highly destructive, cutaneous vasculitis. Abstract  Background There has been a worldwide resurgence of bedbug infestations. Bites by these […]

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