The West Nile virus encephalitis outbreak in the United States (1999-2000): from Flushing, New York, to beyond its borders.

Viruses cause most forms of encephalitis. The two main types responsible for epidemic encephalitis are enteroviruses and arboviruses. The City of New York reports about 10 cases of encephalitis yearly. Establishing a diagnosis is often difficult. In August 1999, a cluster of five patients with fever, confusion, and weakness were admitted to a community hospital in Flushing, New York. Flaccid paralysis developed in four of the five patients, and they required ventilatory support. Three, less severe, cases presented later in the same month. An investigation was conducted by the NewYork City (NYC) and New York State (NYS) health departments and the national Centers for Disease Control and Prevention (CDC). The West Nile virus (WNV) was identified as the etiologic agent. WNV is an arthropod-borne flavivirus, with a geographic distribution in Africa, the Middle East, and southwestern Asia. It has also been isolated in Australia and sporadically in Europe but never in the Americas. The majority of people infected have no symptoms. Fever, severe myalgias, headache, conjunctivitis, lymphadenopathy, and a roseolar rash can occur. Rarely, encephalitis or meningitis is seen. The NYC outbreak resulted in the first cases of WNV infection in the Western Hemisphere and the first arboviral infection in NYC since yellow fever in the nineteenth century. The WNV is now a public health concern in the United States.

The West Nile Virus outbreak of 1999 in New York: the Flushing Hospital experience.

West Nile Virus (WNV) is a mosquito-borne flavivirus, which has been known to cause human infection in Africa, the Middle East, and southwestern Asia. It has also been isolated in Australia and sporadically in Europe but never in the Americas. Clinical features include acute fever, severe myalgias, headache, conjunctivitis, lymphadenopathy, and a roseolar rash. Rarely is encephalitis or meningitis seen. During the month of August 1999, a cluster of 5 patients with fever, confusion, and weakness were admitted to the intensive care unit of the same hospital in New York City. Ultimately 4 of the 5 developed flaccid paralysis and required ventilatory support. Three patients with less-severe cases presented shortly thereafter. With the assistance of the New York City and New York State health departments and the Centers for Disease Control and Prevention, these were documented as the first cases of WNV infection on this continent.

Vibrio cholerae 01 isolated in the gallbladder of a patient presenting with cholecystitis.

Cholera is a topical infection of the intestinal tract and rarely causes extraintestinal disease. The gallbladder has been proposed to be the reservoir of this organism. We present a patient from Bolivia who developed symptoms of acute cholecystitis and whose bile culture grew Vibrio cholerae 01 El tor.

Ramsay Hunt syndrome presenting as a cranial polyneuropathy.

Ramsay Hunt syndrome is herpes zoster of the facial nerve, frequently associated with VIII cranial nerve involvement, but on rare occasions V, VI, IX, and X cranial nerves are affected as well. We present a case of a Ramsay Hunt syndrome with involvement of V, VII, and VIII cranial nerves.

Mycobacterium avium-intracellulare complex pneumonia in a non-HIV-infected individual: an increasingly recognized disease.

In the past, Mycobacterium avium complex (MAC) was considered a colonizing microbe in the immunocompetent host. Today it should be considered a potential pathogen. We present a case of MAC necrotizing pneumonia in a 27-year-old man who tested negatively for the human immunodeficiency virus, had no typical granulomas, and responded rapidly to antimicrobial therapy.

Probable transfusion-associated graft-versus-host disease in a patient with tuberous sclerosis.

Acute transfusion-associated graft-versus-host disease (TA-GVHD) is rare but often fatal. Graft-versus-host disease that occurs as a complication of bone marrow transplantation is more common but has lower mortality. Features of TA-GVHD are nonspecific and can be confused with viral infections and drug reactions. We present a case of probable TA-GVHD in a patient with tuberous sclerosis who survived and was subsequently given irradiated blood without any further adverse events.

Light and electron microscopic identification of Cyclospora species in the small intestine. Evidence of the presence of asexual life cycle in human host.

This is the first case of cyclosporiasis in which the parasite was clearly demonstrated in a duodenal biopsy by light microscopy. Electron microscopy identified the stages of sporozoite, trophozoite, schizont, and merozoite. Although only asexual forms were identified in our case, the sexual cycle must have taken place in the human host, because oocysts were detected in stools of the patients. Therefore, it appears that Cyclospora species require only a single host to complete its entire life cycle. Despite the heavy infection, only enterocytes were invaded. The lamina propria and submucosa were not involved. The morphology of Cyclospora in the intestine is similar to that of Isospora, but differs from that of Cryptosporidium. The morphology of the oocyst of Cyclospora resembles that of Cryptosporidium, but differs from that of Isospora. Thus, a combined study of both stool and intestinal biopsy should readily distinguish Cyclospora from Cryptosporidium and Isospora.

Bilateral sternoclavicular joint septic arthritis presenting as cutaneous abscesses.

The sternoclavicular joint can be involved in ankylosing spondylitis as well as in rheumatoid and degenerative arthritis. Septic arthritis of this joint is infrequently seen, and the diagnosis of this infection can be missed until it presents with a complication. We describe a patient with bacteremia whose presentation of bilateral sternoclavicular joint septic arthritis was multiple cutaneous abscesses on her chest wall.

Reversible seizures and mental status changes in a dialysis patient on isoniazid preventive therapy.

OBJECTIVE: To report a case of reversible seizures and mental status changes in a dialysis patient given preventive isoniazid therapy. CASE SUMMARY: A 66-year-old woman on continuous ambulatory peritoneal dialysis (CAPD) was given isoniazid prophylaxis following a purified protein derivative (PPD) reaction greater than 20 mm in duration. Oral administration of isoniazid 300 mg/d was started and four days later she was admitted to the hospital for confusion, lethargy, and focal seizures that began 24 hours after initiation of therapy. All medications were discontinued with the exception of oral pyridoxine 50 mg/d. Dialysis was withheld to determine if the seizures were medication induced rather than uremia related. Seizures and mental status changes were reversed with pyridoxine. Dialysis was restarted after the symptoms resolved. CONCLUSIONS: Preventive therapy against tuberculosis with isoniazid should be stressed throughout the medical community. Isoniazid has adverse effects including hepatitis and peripheral neuropathy (common) and convulsions (rare). Our experience suggests that additional supplementation with pyridoxine 50 mg/d should be given routinely to prevent adverse reactions in uremic patients.

Shark oil pneumonia. An overlooked entity.

Nonprescription drugs are often believed to be innocuous. We present a case of lipoid pneumonia from ingestion of squalene, a derivative of shark liver oil, a popular over-the-counter Asian folk remedy.

Cutaneous tuberculosis: a rare presentation of malignancy.

An 88-year-old woman presented with fever, a neck ulcer, and multiple subcutaneous nodules on her upper extremities and thorax. Her condition was initially diagnosed as malignancy associated with metastatic disease to the skin. A subcutaneous nodule was aspirated. A gram stain of the aspirate revealed weakly gram-positive bacilli, and a stain for acid-fast bacilli was positive. Mycobacterium tuberculosis was isolated from a culture of a specimen of the skin lesion.