Hypogammaglobulinaemia in adults (found on electrophoresis)

Laboratory tests

• Serum immunoglobulins (IgG, IgA and IgM)
• Serum protein immunofixation
• FBC
• Urine protein:creatinine ratio (spot sample)
• Serum creatinine with eGFR
• HIV serology
• Anti-tetanus antibodies (vaccine response)

Repeat later

• Serum immunoglobulins (IgG, IgA and IgM): repeat (if the first result is low, with no obvious cause)if needednon-French guidelineA primary immunodeficiency is considered only if IgG and IgA are low on at least two occasions, secondary causes having been excluded ^[2].

Laboratory tests (rapid)

• FBC
• Serum immunoglobulins (IgG, IgA and IgM)
• Serum protein immunofixation
• Urine protein:creatinine ratio (spot sample)
• Serum creatinine with eGFR
• Serum calcium
• LDH
• Urine protein electrophoresisif neededProteinuria present (Bence Jones testing is done only above 50 mg/L according to the NABM ^[4]): proteinuria without albuminuria with hypogammaglobulinaemia suggests light-chain myeloma ^[3].
• Urine immunofixation (Bence Jones proteinuria)if neededProteinuria present (Bence Jones testing is done only above 50 mg/L according to the NABM ^[4]): proteinuria without albuminuria with hypogammaglobulinaemia suggests light-chain myeloma ^[3].
• Blood lymphocyte immunophenotypingif neededLymphocytosis: suspected chronic lymphocytic leukaemia ^[3].
• Serum free kappa and lambda light chains (if light-chain myeloma suspected)if needednon-French guidelineNICE pairs them with electrophoresis to confirm a monoclonal component ^[11] and requests them from primary care onwards after age 60 for persistent bone pain or unexplained fracture ^[12]. The HAS reserves their prescription for the specialist, the technique not being listed in the French laboratory fee schedule (NABM) ^[13], and it is not established that they should replace the search for proteinuria ^[3]. An electrophoresis without a narrow peak does not rule out light-chain myeloma ^[13].

Before the first infusion

• Serum immunoglobulins (IgG, IgA and IgM)