R16.1Splenomegaly, not elsewhere classified

R16.1 is the ICD-10-CM diagnosis code for splenomegaly, not elsewhere classified. It belongs to category R16 (Hepatomegaly and splenomegaly, not elsewhere classified), block R10-R19 (symptoms and signs involving the digestive system and abdomen) and chapter 18 (symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified). It is billable, so it can be reported on its own for dates of service from October 1, 2026 through September 30, 2027.

Within R16 (Hepatomegaly and splenomegaly, not elsewhere classified), R16.1 is specifically for splenomegaly, not elsewhere classified. Related codes cover Hepatomegaly, not elsewhere classified (R16.0) and Hepatomegaly with splenomegaly, not elsewhere classified (R16.2).

It is not a CC or MCC, so as a secondary diagnosis it doesn't change the MS-DRG severity level.

In MS-DRG v44.0, it is part of the grouping logic for DRG 814 (Reticuloendothelial and Immunity Disorders with MCC, relative weight 2.0729), DRG 815 (Reticuloendothelial and Immunity Disorders with CC, relative weight 1.0444) and DRG 816 (Reticuloendothelial and Immunity Disorders without CC/MCC, relative weight 0.7381), in MDC 16 (Diseases and Disorders of the Blood and Blood Forming Organs and Immunological Disorders), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.

It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.

Before ICD-10, this condition was coded in ICD-9-CM as 789.2 (splenomegaly).