Acquired partial lipodystrophy is characterized clinically by the gradual onset of bilaterally symmetrical loss of subcutaneous fat from the face, neck, upper extremities, thorax, and abdomen, in the 'cephalocaudal' sequence, sparing the lower extremities (summary by Misra et al., 2004). The disorder is not inherited in a classic mendelian pattern; it rather represents a phenotype with a complex etiology. Affected individuals may have genetic susceptibility factors that require the additional presence of environmental factors or acquired disorders to be expressed (summary by Hegele et al., 2006). Most cases are sporadic, family history is negative, and females are more often affected than males (ratio, 4:1). The disease or phenotype is Experimental Factor Ontology entry EFO_0020027 (susceptibility to partial acquired lipodystrophy). Also known as: APLD, APLD, susceptibility to, Barraquer-Simons syndrome, lipodystrophy, cephalothoracic type, partial progressive lipodystrophy.