2026 ICD-10-CM Diagnosis Code K90.9Intestinal malabsorption, unspecified
ICD-10-CM Codes›K00–K95›K90-K95›K90
- Billable — Valid for Submission
- CC — Complication or Comorbidity
- Chronic Condition
K90.9 is a billable ICD-10-CM diagnosis code for intestinal malabsorption, unspecified. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 391 through 392. As a secondary diagnosis, it counts as a complication or comorbidity (CC) and moves an inpatient stay to a higher severity level within its MS-DRG family. It does not count, however, when the principal diagnosis is one of 14 closely related codes. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Other specified and unspecified gastrointestinal disorders.
K90.9 does not risk-adjust for Medicare Advantage under the CMS-HCC V28 model. It still risk-adjusts in the RxHCC Part D (V08) category 66 for payment year 2026.
Code Identity
Code Classification
Medicare Risk Adjustment (HCC)Billing
K90.9 does not risk-adjust for Medicare Advantage under the CMS-HCC V28 model, but it maps to payment categories in the other CMS models shown below.
Source: CMS Payment Year 2026 risk adjustment mappings and model software. Weights are relative factors, not dollar amounts; a beneficiary's total RAF also includes demographics and interactions. Browse all CMS-HCC categories.
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Abnormal intestinal absorption
- Chronic steatorrhea
- Deficiency of coagulation factor due to vitamin K deficiency
- Disorder of gastrointestinal tract co-occurrent with human immunodeficiency virus infection
- Fatty stool
- Folate deficiency anemia due to malabsorption
- Gastrointestinal malabsorption syndrome co-occurrent with human immunodeficiency virus infection
- Gastrointestinal sequelae of disorders
- Gastrointestinal test finding
- Hyperparathyroidism due to intestinal malabsorption
- Intestinal malabsorption
- Intestinal malabsorption due to bile acid synthesis defect
- Intolerance to monosodium glutamate
- Intolerance to substance
- Malabsorption caused by infective agent
- Malabsorption syndrome
- Malabsorption syndrome due to acquired intolerance to fructose
- Malabsorption syndrome due to intolerance to lactose
- Megaloblastic anemia due to impaired absorption of folate
- Osteoporosis due to malabsorption
- Post-infective malabsorption
- Primary malabsorption of infancy
- Vitamin K deficiency coagulation disorder due to malabsorption
Index to Diseases and InjuriesGuidance
Alphabetical index entries that point to this code.
Disturbance (s) See Also: Disease;
absorption K90.9
assimilation, food K90.9
Malabsorption K90.9
intestinal K90.9
syndrome K90.9
Malassimilation K90.9
Steatorrhea (chronic) K90.9
Syndrome See Also: Disease;
malabsorption K90.9
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Clinical InformationClinical
Intolerance to Substance
an individual has an inability to process a substance without adverse effects.
Patient EducationClinical
Malabsorption Syndromes
Your small intestine does most of the digesting of the foods you eat. If you have a malabsorption syndrome, your small intestine cannot absorb nutrients from foods.
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert K90.9 to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About K90.9Overview
What is the ICD-10 code for intestinal malabsorption, unspecified?
The ICD-10-CM code for intestinal malabsorption, unspecified is K90.9 (sometimes written as K909). It is billable on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
Is K90.9 (Intestinal malabsorption) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report intestinal malabsorption, unspecified on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What MS-DRG does K90.9 group to?
When intestinal malabsorption, unspecified is the principal diagnosis on an inpatient stay, it groups to MS-DRG 391, 392, with relative weights from 0.7796 to 1.2683 depending on complications. Higher weights mean higher Medicare reimbursement.
Is K90.9 a CC or MCC?
CMS lists K90.9 as a CC (complication or comorbidity) for FY 2026. Reported as a secondary diagnosis, it moves the inpatient stay to a higher-weighted DRG within its severity family. It does not count when the principal diagnosis is one of the 14 closely related codes in its exclusion list.
What is the ICD-9 equivalent of K90.9?
Under the General Equivalence Mappings, intestinal malabsorption, unspecified converts to ICD-9-CM 579.9 (intest malabsorption NOS). The mapping is a direct match.
Does K90.9 risk-adjust for Medicare Advantage payment?
Not for Medicare Advantage: K90.9 maps to no category in the CMS-HCC V28 model. It still risk-adjusts in the RxHCC Part D (V08) category 66 (Pancreatic Disorders and Intestinal Malabsorption, Except Pancreatitis).
