Cryptococcus neoformans, a yeast-like fungus, causes a lung infection thought to be acquired by inhalation. The organism has been isolated from several natural environments, especially where weathered pigeon droppings accumulate.

This test detects antibodies present in Cryptococcus infections. It appears that about 50% of patients who present with antibodies have a predisposing condition such as lymphoma or sarcoidosis or are being treated with steroid therapy. Infection with C. neoformans has long been associated with Hodgkin disease and other malignant lymphomas. In fact, C. neoformans, in conjunction with malignancy, occurs to such a degree that some researchers have raised the question regarding the possible etiologic relation between the two diseases. Tests ordered for this disease include LA testing for antigens or antibodies.

• Negative for Cryptococcus antibody by IFA or tube agglutination (TA)

• IFA test has a specificity of 77%.

• TA test has a specificity of 89%.

1. Collect a 7-mL blood serum sample in a red-topped tube. A 2-mL CSF sample may also be used. Observe standard precautions.

2. Label the specimen with the patient’s name, date, and test(s) ordered and place in a biohazard bag for transport to the laboratory.

1. Positive C. neoformans tests are associated with infections of the lower respiratory tract through inhalation of aerosols containing C. neoformans cells disseminated by the fecal droppings of pigeons.

2. TA titers ≥1.2 are suggestive of infection.

Pretest Patient Care

1. Explain test purpose and procedure. Obtain clinical history and assess for exposure.

2. Follow guidelines in Chapter 1 for safe, effective, informed pretest care.

3. Specimens for culture of the organism may also be required.