Blood-high-viscosity-syndrome

Heavy-Chain Disease. Rarely, unusual forms of IgG, IgA, or light chains polymerize and cause a similar syndrome with high blood viscosity. Heavy-chain diseases in which the paraprotein consists only of a heavy chain, usually incomplete, are rare conditions associated with lymphoid infiltration. The most common of these is a-chain disease, in which the intestine is infiltrated and severe malabsorption may be seen. 

---