Patients with organic acidemia are prone to different
infections, which lead to
acidosis episodes. Some studies have evaluated the status of immune system in acidotic phase in these patients, but to the best of our knowledge no study has evaluated the immune system in non-acidotic phase of the disease. In this study, thirty-one patients with organic acidemia were enrolled. For evaluation of humoral immunity, serum
IgA,
IgG,
IgE,
IgM, isohemaggltuinin titer, anti
tetanus and anti
diphtheria IgG were measured. For screening of
complement deficiencies, serum C3, C4, and CH50 were assessed. Eleven patients had
Maple Syrup Urine Disease (MSUD), 10 had
methylmalonic acidemia, 5 had
isovaleric acidemia, 4 had glutaric aciduria, and 1 had
propionic acidemia. Serum
IgM level was less than normal in 2 patients. Serum isohemagglutinin titer was less than 1:8 in 2 other patients.
IgA,
IgE, and
IgG were within normal range for all patients. Anti
tetanus and anti
diphtheria IgG levels were low in two patients with MSUD. No significant relationship was found between any of the measured parameters and history of recurrent admissions,
recurrent infections and the type of their diseases. Five patients had high C3 level, 4 had high C4 level, and 5 had high CH50 percentage. Totally, 10 patients had high
complement level, but no remarkable connection was noted between the type of the disease and
complement level. Minor insignificant deficiencies in humoral immunity in non-acidotic phase of organic acidemia were found. Some components of
complement system showed increase in some patients, which might be due to decreased pH in extracellular fluid.