Occult pneumonia

Occult pneumonia is a pneumonia that is not observable directly by the eye, but can only be shown indirectly, especially by radiography. Occult pneumonia can be made visible by chest X-rays.

The general symptoms cough for more than 10 days and fever for more than 3 days can indicate the presence of occult pneumonia, just as a temperature of 39 °C or higher and a high white blood cell count.^[1]

Administration of a pneumococcal vaccine decreases the incidence of occult pneumonia, which suggests that Streptococcus pneumoniae is a cause of occult pneumonia. Occult pneumonia, however, can also be the result of atypical pneumonia.^[2]

Chest x-ray, showing pneumonia in right lower lobe.

Although pneumococcal vaccination lowers the prevalence of occult pneumonia, it does not make radiographic diagnosis superfluous at patients with prolonged fever, cough or leukocytosis.^[1][3]

Etymology: the term is derived from the Latin occultus = hidden, secret and pneumonia = inflammation of the lungs > Greek: pneuma = wind and Indo-European: pleumon = floating, swimming.^[4][5]

See also

• Fecal occult blood