Lymphopoenia in children

Key words: Children, Lymphopoenia, Primary immunodeficiencies, Infections

Isolated lymphopoenia is a common finding in children evaluation. Usually, lymphopoenia is observed in children with infectious or autoimmune diseases, with nutritional disorders or under treatment with immunosuppressive drugs. However, persistence of low lymphocyte counts, especially when associated with invasive or opportunistic infections, eczema, diarrhoea, failure to thrive, lymphadenopathy or splenomegaly, should lead to suspect lymphopoenia as manifestation of primary immunodeficiencies. In this context, patients with lymphopoenia should be evaluated by analysis of serum immunoglobulins, lymphocyte subpopulations and genetic studies. Secondary lymphopoenia is usually responsive to the treatment of the primary disease, while idiopathic lymphopoenia will require close clinical and laboratory monitoring and anti-microbial prophylaxis. Genetic diagnosis is important to evaluate the clinical prognosis and develop specific treatment that might include in selected case haematopoietic stem cell transplantation, or substitutive enzyme therapy.