Monoclonal Gammopathy with Systemic Amyloidosis: An Evaluation of Diagnostic Elements

Monoclonal gammopathies result from an overproduction of a single abnormal clone of plasma cell or B lymphocyte that produce an immunologically homogenous immunoglobulin (Ig) commonly referred to as paraprotein or monoclonal (M) protein. The circulating M-protein may consist of an intact immunoglobulin, the light chain only, or (rarely) the heavy chain only. The heavy chain is from one of the five immunoglobulin classes G, A, M, D or E, while the light chain is either kappa (κ) or lambda (λ) in type. Accurate detection and quantitation of monoclonal immunoglobulins is important for the diagnosis and management of monoclonal gammopathies. We report a case of a 71 year old lady with a history of chronic gastritis and recurrent lower respiratory tract infection whereby no specific diagnosis was made until a computed tomography (CT) guided lung biopsy and orogastroduodenoscopy (OGDS) 5 years later from the onset of initial symptoms revealed pulmonary and gastric amyloidosis, respectively.