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Although Mycobacterium tuberculosis primarily causes disease in humans, many animals are reported to be susceptible to infection, including primates, swine, cattle, sheep, goats, dogs, cats, and elephants (3, 8). Infection with M. tuberculosis in birds is rare. Psittacine birds (principally the parrot family) are the only avian species known to become infected with M. tuberculosis, presumably due to close contact with tuberculous owners. There are four reports of infection in Amazon parrots: one each in a mealy parrot (1), a yellow-naped parrot (10), and a red-lored parrot (2) and one in an Amazon parrot which was not further identified (4). All of the parrots presented with cutaneous growths on the head and neck and had localized granulomas in the eye and retrobulbar tissues, the sinuses and nares, and the oral cavity. Two parrots were found to have systemic infections at necropsy (1, 4). The birds had no known contact with humans with tuberculosis.

This report describes disseminated M. tuberculosis disease in another psittacine bird, a green-winged macaw, and notes a possible human source of the infection. This report has implications for public health in that human-to-bird and, possibly, bird-to-human transmission of tuberculosis could create a perpetual reservoir of untreated tuberculosis.

Case report. An adult, imported green-winged macaw (Ara chloroptera) had been ill for several months with progressive eyelid swelling, intermittent diarrhea, occasional loud respiratory sounds, listlessness, and poor feeding. The bird had lived in a multiple-person household in New York City for at least 6 years. Several months prior to the presentation described here the bird had been evaluated for tachypnea by a veterinarian. At that time, specimens from facial lesions were positive for acid-fast bacilli on microscopic examination, but culturing was not performed. The owner was advised to euthanatize the bird but chose not to do so.

Microbiology. Acid-fast bacilli were seen in auramine acid-fast stains of biopsied tissue from the eyelid, tongue, and skin. Specimens were processed and inoculated into BACTEC 12B broth bottles (Becton Dickinson, Diagnostic Instrument Systems, Sparks, Md.) and onto Middlebrook 7H11 agar plates (Becton Dickinson Microbiology Systems, Cockeysville, Md.). In approximately 2 weeks, cultures were positive and the organism was identified as M. tuberculosis by conventional biochemical tests, including niacin production, nitrate reduction, and growth on thiophene-2-carboxylic acid hydrazide medium. A DNA probe for M. tuberculosis complex was positive (GenProbe, San Diego, Calif.). A standardized IS6110-based Southern blot hybridization protocol was used to determine the genotype of the isolate. Restriction fragment length polymorphism analysis revealed a three-banded pattern that is the most common pattern in New York City. The organism was susceptible when tested by the radiometric antimicrobial susceptibility test system (BACTEC) to ethambutol, isoniazid, pyrazinamide, rifampin, and streptomycin.

Epidemiology. Review of the New York City tuberculosis registry and hard copies of Department of Health records revealed that two people with a history of culture-confirmed pulmonary tuberculosis resided at the address listed for the bird's owner. They had extensive contact with the bird while they were potentially infectious, including placing food between their lips for the bird to grasp. The first person had drug-treatable tuberculosis diagnosed in 1991 and did not adhere to treatment but ultimately completed treatment while incarcerated. The second person's disease was diagnosed in January 1992, but the isolate was not tested for antimicrobial susceptibility. The patient completed a full course of antituberculosis treatment.

Necropsy. The bird was seized and euthanatized under the authority of the New York City Health Code after the owner refused multiple requests to have the bird euthanatized. Necropsy revealed miliary granulomatous pneumonia, hepatitis, stomatitis, glossitis, myocarditis, endocarditis, and conjunctivitis. Acid-fast bacilli were identified in the lung, liver, and skin lesions. Histopathology revealed classic tuberculous nodules with a central necrotic core surrounded by epithelioid macrophages, multinucleated giant cells, and a fibrous capsule. There was no mineralization. Specimens from the lungs and skin were culture positive for M. tuberculosis, and the antimicrobial susceptibility and restriction fragment length polymorphism patterns of the postmortem isolates were identical to those of the antemortem isolates.

Discussion. Birds can have avian, bovine, and human tuberculosis. More recently, disseminated disease with the emerging human pathogen Mycobacterium genavense has been reported for a variety of birds (5-7, 9). Mycobacterial infections in nonpsittacine birds are usually caused by the ubiquitous soil and water organism Mycobacterium avium (3, 8), and the route of infection is usually the alimentary tract. Most lesions develop in the intestinal tract, liver, and spleen. Birds only occasionally suffer from pulmonary M. avium disease.