Multiple myeloma is a neoplastic plasma cell disorder characterized by clonal proliferation of malignant plasma cells in the bone marrow microenvironment, monoclonal protein in the blood or urine, and associated organ dysfunction (Palumbo and Anderson, 2011).

Familial Mediterranean fever (FMF) is divided into two phenotypes: type 1 and type 2. FMF type 1 is characterized by recurrent short episodes of inflammation and serositis including fever, peritonitis, synovitis, pleuritis, and, rarely, pericarditis and meningitis. The symptoms and severity vary among affected individuals, sometimes even among members of the same family. Amyloidosis, which can lead to kidney failure, is the most severe complication, if untreated. FMF type 2 is characterized by amyloidosis as the first clinical manifestation of FMF in an otherwise asymptomatic individual.

Hereditary transthyretin amyloidosis (ATTRv amyloidosis) is characterized by a slowly progressive peripheral sensorimotor and/or autonomic neuropathy. Amyloidosis can involve the heart, central nervous system (CNS), eyes, and kidneys. The disease usually begins in the third to fifth decade in persons from endemic foci in Portugal and Japan; onset is later in persons from other areas. Typically, sensory neuropathy starts in the lower extremities with paresthesia and hypesthesia of the feet, followed within a few years by motor neuropathy. In some persons, particularly those with early-onset disease, autonomic neuropathy is the first manifestation of the condition; findings can include orthostatic hypotension, constipation alternating with diarrhea, attacks of nausea and vomiting, delayed gastric emptying, sexual impotence, anhidrosis, and urinary retention or incontinence. Cardiac amyloidosis is mainly characterized by progressive restrictive cardiomyopathy. Individuals with leptomeningeal amyloidosis may have the following CNS findings: dementia, psychosis, visual impairment, headache, seizures, motor paresis, ataxia, myelopathy, hydrocephalus, or intracranial hemorrhage. Ocular involvement includes vitreous opacity, glaucoma, dry eye, and ocular amyloid angiopathy. Mild-to-severe kidney disease can develop.

Multiple self-healing palmoplantar carcinoma (MSPC) is characterized by recurrent keratoacanthomas in palmoplantar skin as well as in conjunctival and corneal epithelia. In addition, patients experience a high susceptibility to malignant squamous cell carcinoma (summary by Zhong et al., 2016).

Hereditary amyloidosis is an autosomal dominant disorder in which amyloid deposition occurs in various tissues. Hereditary systemic amyloidosis-3 (AMYLD3) is characterized by a wide clinical spectrum including amyloid neuropathy, nephropathy, hepatopathy, and cardiomyopathy. Amyloid deposition can also occur in skin, larynx (resulting in hoarseness), and testis (resulting in infertility) (summary by Hamidi Asl et al., 1999, Lachmann et al., 2002). For a discussion of genetic heterogeneity of hereditary systemic amyloidosis, see AMYLD1 (105210).

Hereditary systemic amyloidosis-5 (AMYLD5) is a rare amyloidosis that can affect the viscera, with severe involvement when located in the kidneys and liver. Renal dysfunction of varying severity may be the predominant manifestation. Massive hepatic hemorrhage constitutes the other severe visceral involvement. Dermatologic manifestations are rare (summary by Granel et al., 2005). The various forms of hereditary systemic amyloidosis that do not have peripheral neuropathy as part of the clinical syndrome had been referred to as 'Ostertag type' (Benson, 2005). For a discussion of genetic heterogeneity of hereditary systemic amyloidosis, see AMYLD1 (105210).