Internal Medicine

0521779407-20 CUNY1086/Karliner 0 521 77940 7 June 4, 2007 21:22

1438 Toxoplasmosis

■Neonatal toxoplasmosis: variable picture from few findings to severe

illness. May see chorioretinitis, encephalitis, hepatosplenomegaly,

rash, fever, hydrocephalus, lymphadenopathy.

■Acute infection in pregnancy: fetus infected in 10–25% of first

trimester infections, rising to 65% for third trimester, but babies

infected in third trimester usually clinically normal or near normal

at term.

tests

■Basic tests: blood: Acute infection: CBC shows atypical lymphocyto-

sis, increased monocytes. LFTs may be mildly abnormal.

■Basic tests: urine: not helpful

■Specific tests: Serology, using ELISA, useful. IGG rises early and usu-

ally positive at time of symptoms. Presence of IGM confirms acute

infection. Biopsy of lymph node shows characteristic morphology

(highly suggestive but not diagnostic), and sometimes parasite cysts

seen.

■Other tests: Chest X-ray can show interstitial infiltrate. For cerebral

toxoplasmosis in AIDS, MRI more sensitive than CT.

differential diagnosis

■Acute infection: infectious mononucleosis, CMV infection, lym-

phoma.

■Congenital infection: CMV disease, rubella, syphilis, tuberculosis.

management

What to Do First

■Assess organs involved. Neonatal case may need IVs, nutritional help

General Measures

■Teach patient and family about epidemiology

specific therapy

Indications

■Clinically ill acute case, neonatal disease, active chorioretinitis, any

immunocompromised patient, and infection acquired during preg-

nancy (if abortion not requested).

Treatment Options

■Pyrimethamine plus:

■Sulfadiazine

■Folinic acid

■Another regimen: clindamycin plus pyrimethamine and folinic acid