Diagnostik af Pneumocystis carinii pneumoni hos HIV-positive patienter. Den diagnostiske vaerdi af induceret sputum og cykeltest

The object of investigation is to illustrate the values of two noninvasive procedures: the induced sputum test and the exercise test in the diagnosis of Pneumocystis carinii pneumonia (PCP). Both of the procedures are described. Fifty HIV-positive men in whom interstitial pneumonia was suspected participated. PCP was diagnosed in 16 patients, in ten of these by the induced sputum test, the sensitivity of which is, therefore, 35-85% (95% confidence limits). The exercise test, an investigation for demonstration of exercise induced oxygen desaturation, was of good predictive value. Thus, seven out of nine patients with positive exercise test results had PCP as compared with two out of 19 with normal exercise test results, p = 0.0009. The sensitivity was thus 40-97%. In five out of the six patients with false negative results to the induced sputum test, the exercise test was performed and was positive in all of the case. The method is rapid and simple and merely requires access to an exercycle and a pulse-oxymeter preferably with a recorder. It is concluded that the exercise test and the induced sputum test are valuable investigations which supplement one another in cases of suspected PCP and which avoid the need for bronchoscopy in 53-80% of the patients.