Fig. 6.42. A The distribution of skeletal lesion in 20 patients with disseminated coccidioidomycosis. B A cutaneous lesion in disseminated coccidiodomycosis: there are usually well circumscribed and contain many fungi. (A Courtesy of Dr. J. P. McGahan, Sacramento)

Clinical Characteristics

Coccidioidomycosis can cause a wide variety of signs or symptoms or have no clinical affect. In most individuals the only result of exposure to C. immitis is conversion of the skin test without any symptoms. In some patients there may be a tiny calcified granuloma or fibrotic scar or cavity, visible on a routine chest radiograph and representing a pulmonary residuum.

In patients in whom there are clinical smyptoms, the common diagnosis is "flu;' with a mild fever, pleuritic chest pain, generalized aches and pains, night sweats and chills, and a cough. Some patients may have a fine diffuse transient erythematous rash covering the body and limbs, and may develop erythema nodosum or erythema multiforme. These are "the bumps;" itchy, tender nodules of varying size. There is often arthralgia, without effusion (desert rheumatism). In such patients the skin test often causes a violent reaction. Most patients improve clinically and return to health after 3 or 4 weeks. If symptoms persist for 6-8 weeks, there is said to be persistent coccidioidomycosis.

A few patients develop the rare primary cutaneous lesions, which resemble a chancre at the site of inoculation. This is followed by regional lymphadenopathy. However, most cutaneous lesions (nodules, ulcers, and pustules) are the result of dissemination of infection from a primary pulmonary site. Such dissemination may result in single or multiple cutaneous lesions, some of which may spread extensively over the skin. Pulmonary cavities may persist without general dissemination, but with recurrent complaints of cough and hemoptysis, and may lead to a pneumothorax.

The most serious pattern of infection is extrapulmonary dissemination, which is more common in some communities than in others. It is ten times more common in blacks, Filipinos, other Asians, Eskimos, and American Indians. It is much less common in Caucasian females than in Caucasian males, but if the patient is pregnant, then the later the infection starts, the more likely is dissemination and the prognosis worsens accordingly.

Any immunodeficient patient is liable to develop disseminated coccidioidomycosis: not only those with AIDS, but immunosuppressed transplant patients, and those receiving corticosteroid or chemotherapy. It has been suggested that the size of the initial dose of spores is significant, with a heavy load increasing the risk of subsequent dissemination. This has not been verified in humans.

Disseminated coccidioidomycosis usually involves the bones (Fig. 6.42 A), joints, skin (Fig. 6.42 B), meninges, and the urinary tract. It can involve any organ in the body although the gastrointestinal tract and endocardium are seldom infected. Chronic meningitis develops in about 30% of those with disseminated infection, but the onset may be difficult to recognize: the early symptoms are ill health, personality change, and headache. The brain is seldom involved, but without treatment the meningitis is invariably fatal.