Mumps mistaken for rubella in the first trimester of pregnancy. The role of the microbiology laboratory in the diagnosis of the infection. A case report.

A case of mumps with an exanthema is described. However, the parotid swelling was mistaken for enlarged lymph nodes, and the case was described as one of "typical rubella". As the patient was pregnant in her first trimester, an induced abortion was considered. Serum specimens for rubella antibody testing had been taken, but the information given by the consulting physician was incorrect and led to testing for past infection and immunity. After re-examination of the patient by a gynaecologist, mumps was suspected and the diagnosis verified serologically. The present case shows that in certain situations adequate information must be given to the laboratory in order to ensure a meaningful interpretation of the results of the serological examination.