[Mixed connective tissue disease revealed by chronic lymphocytic meningitis in an infant].

UNLABELLED: Mixed connective tissue disease (MTCD) is a systemic inflammatory disorder individualised by Sharp et al. in 1972. This entity is rare in children.

CASE REPORT: We report an exceptional case of MTCD revealed by lymphocytic meningitis in a two-month-and-a-half-old infant. The disease was diagnosed at the age of nine months when clinical symptomatology was completed by common signs of the illness (Raynaud's phenomenon, swollen hands), systemic lupus erythematosus-like symptoms (lymphadenopathy, squamous erythema of the limbs, hepato-splenomegaly, pleuritis and ascites) and polymyositis-like findings (muscle weakness with increased serum levels of myogenic enzymes). Laboratory investigations showed an important inflammatory syndrome and the presence of speckled anti-nuclear and anti-U(1)RNP antibodies. Specific antibodies of the other connective tissue diseases were also positive (anti-DNA, anti-Sm, anti-SSA and SSB, anti-Scl 70 and JO1) pleading for the mixed feature of the illness. The follow-up after corticosteroid treatment was marked by clinical and biological improvement. But after five months, the patient died following a severe infectious complication.

CONCLUSION

Chronic lymphocytic meningitis can be part of Sharp's syndrome even in infants. However, the diagnosis relies on the evidence of characteristic clinical and biological abnormalities of MTCD.