Case records of the Massachusetts General Hospital. Weekly clinicopathological exercises. Case 5-1992. A 20-year-old man with diffuse pulmonary infiltrates and disseminated intravascular coagulation

Mycoplasma pneumoniae and its role as a human pathogen

Mycoplasma pneumoniae is a unique bacterium that does not always receive the attention it merits considering the number of illnesses it causes and the degree of morbidity associated with it in both children and adults. Serious infections requiring hospitalization, while rare, occur in both adults and children and may involve multiple organ systems. The severity of disease appears to be related to the degree to which the host immune response reacts to the infection. Extrapulmonary complications involving all of the major organ systems can occur in association with M. pneumoniae infection as a result of direct invasion and/or autoimmune response. The extrapulmonary manifestations are sometimes of greater severity and clinical importance than the primary respiratory infection. Evidence for this organism's contributory role in chronic lung conditions such as asthma is accumulating. Effective management of M. pneumoniae infections can usually be achieved with macrolides, tetracyclines, or fluoroquinolones. As more is learned about the pathogenesis and immune response elicited by M. pneumoniae, improvement in methods for diagnosis and prevention of disease due to this organism may occur.

Fatal disseminated intravascular coagulation caused by Mycoplasma pneumoniae

We report fatal disseminated intravascular coagulation caused by Mycoplasma pneumoniae infection in a 7-year-old white boy. The diagnosis was based on relevant clinical material, absence of any other infections, a 4-fold rise in titer of complement fixation for M. pneumoniae and open lung biopsy findings. We discuss the association between M. pneumoniae and autoimmune mechanism.

Multiple brain abscesses and bacteremia in a child due to Fusobacterium necrophorum

A case of Fusobacterium necrophorum bacteremia and multiple brain abscesses in a 6-year-old child following a Mycoplasma pneumoniae infection is described. Brain abscess due to this microorganism has only been described in three other cases since 1977. The clinical picture was consistent with postanginal septicemia, with septic metastatic complications normally only seen in teenagers and young adults. The patient was successfully treated with a 2-month course of parenteral penicillin G and metronidazole.