Reference ranges for IgG, IgM and IgA in the serum of urban and rural Somalis

In order to provide baseline data for an immuno-parasitological laboratory in Somalia, serum concentrations of IgG, IgM and IgA were determined in some key populations: healthy residents of Mogadishu (n = 157), inhabitants of the village of Daimo Samo (n = 276) and patients with malaria (n = 39) and visceral leishmaniasis (n = 26), both protozoan infections accompanied by hypergammaglobulinaemia and causing severe health problems in Somalia. Since the serum immunoglobulin concentrations in the Somali populations studied were not normally distributed, they were evaluated using medians and percentiles. Significantly higher values of IgG, IgM and IgA were demonstrated in healthy Mogadishu residents as compared to healthy Swedes. Daimo Samo villagers had significantly higher IgG and IgM values than healthy Mogadishu residents. Very high concentrations of IgG and IgM were demonstrated in sera from patients with visceral leishmaniasis. Somali patients with malaria also had marked hypergammaglobulinaemia, however, only in the IgG class. The high levels of IgG, IgM and IgA demonstrated in sera from Somalis, indicate the need for establishing local reference values and should be considered when introducing serological tests in tropical countries. Such methods are usually adopted to conditions in industrialized countries, where immunoglobulin contents of sera are lower.