What laboratory finding is common to Pneumocystis jirovecii pneumonia and histoplasmosis?

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Multiple Choice

What laboratory finding is common to Pneumocystis jirovecii pneumonia and histoplasmosis?

LDH rises when cells are damaged, and both Pneumocystis jirovecii pneumonia and histoplasmosis cause lung tissue injury with inflammation and cellular breakdown. In PJP, diffuse alveolar damage leads to leakage of LDH into the bloodstream. In histoplasmosis, especially with pulmonary or disseminated involvement, tissue necrosis and macrophage-rich inflammation similarly release LDH. So an elevated LDH is a common laboratory clue for these infections, even though it’s not specific. By contrast, a low or normal LDH wouldn’t fit the typical pattern, and CRP, while often elevated in infections, is nonspecific.

LDH rises when cells are damaged, and both Pneumocystis jirovecii pneumonia and histoplasmosis cause lung tissue injury with inflammation and cellular breakdown. In PJP, diffuse alveolar damage leads to leakage of LDH into the bloodstream. In histoplasmosis, especially with pulmonary or disseminated involvement, tissue necrosis and macrophage-rich inflammation similarly release LDH. So an elevated LDH is a common laboratory clue for these infections, even though it’s not specific. By contrast, a low or normal LDH wouldn’t fit the typical pattern, and CRP, while often elevated in infections, is nonspecific.

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