All about Cave disease

The rescue of the boys trapped in a cave in Thailand for two weeks has held the world agog with anticipation and apprehension. The high-risk rescue mission is over and all 11 boys and their coach have been brought out of the cave. Although they appear to be physically unharmed, another danger looms ahead for them. They are at risk of many diseases that they might have been exposed to during the two weeks in the cave.

One amongst the diseases is Histoplasmosis or ‘Cave disease’ or “spelunker’s lung”, as it is popularly known as. Here are some salient facts about ‘Cave disease’.

·         Cave disease is a lung infection caused by the fungus Histoplasma capsulatum, following inhalation of the microscopic fungal spores, often after participating in activities that disturb the soil, particularly soil that is contaminated with bird or bat droppings. Such activities include cleaning chicken coops, construction, digging soil where there are bird or bat droppings or “spelunking” i.e. exploring caves. 

·         Most patients are asymptomatic, while some may have flu-like symptoms, which include fever, cough, fatigue, chills, headache, bodyache. The infection is self-limiting in most cases.

·         Symptoms may appear 3 to 17 days after exposure to the fungus.

·         While the disease is mostly mild in nature, it can be fatal in the immunocompromised persons.

·         Being in the area where the fungus is present increases the risk of developing histoplasmosis. However, infants, adults older than 55 years, immunocompromised individuals such as those who have HIV/AIDS or are taking immunosuppressant drugs (steroids), or have had organ transplant are at a higher risk for developing disseminated histoplasmosis.

·         Histoplasmosis is not contagious.

·         Diagnosis of acute histoplasmosis is done by detection of Histoplasma antigen in urine and/or serum using enzyme immunoassay.

·         Antibody tests are not useful in diagnosing acute histoplasmosis as development of antibodies to Histoplasma can take 2 to 6 weeks.

·         Mild to moderate cases of acute pulmonary histoplasmosis are usually self-limiting.  IDSA recommends itraconzole (200 mg 3 times daily for 3 days and then 200 mg once or twice daily for 6–12 weeks) for patients who continue to have symptoms for more than a month.

·         For moderately severe to severe acute pulmonary histoplasmosis, IDSA recommends lipid formulation of amphotericin B (3.0–5.0 mg/kg daily IV x 1–2 weeks) followed by itraconazole (200 mg 3 times daily x 3 days and then 200 mg twice daily, for a total of 12 weeks).

(Source: CDC)

Dr KK Aggarwal

Padma Shri AwardeeVice President CMAAO

Group Editor-in-Chief IJCP Publications

President Heart Care Foundation of India

Immediate Past National President IMA