I88.9 Nonspecific lymphadenitis, unspecified

ICD-10-CM I88.9: Nonspecific lymphadenitis, unspecified

ICD-10-CM code I88.9 represents nonspecific lymphadenitis, unspecified, an active diagnosis concept classified as a disease or syndrome. It falls under the parent category I88 for nonspecific lymphadenitis within the broader I80-I89 grouping for diseases of veins, lymphatic vessels, and lymph nodes, not elsewhere classified. 1 3

Plain-language overview

Code I88.9 designates nonspecific lymphadenitis, unspecified, functioning as an active terminology record for a diagnosis classified semantically as a disease or syndrome. 1

What this code represents

The diagnosis code I88.9 represents nonspecific lymphadenitis, unspecified, and exists as a narrower concept under the parent code I88 for nonspecific lymphadenitis. 1

Coding details

Code I88.9 is nested within the I80-I89 category for diseases of veins, lymphatic vessels, and lymph nodes, not elsewhere classified, and sits alongside other specific I88 variants. 3

Within the I88 category, I88.9 is distinguished from I88.0 for nonspecific mesenteric lymphadenitis, I88.1 for chronic lymphadenitis except mesenteric, and I88.8 for other nonspecific lymphadenitis. 3

Documentation considerations

The terminology record identifies I88.9 as an unspecified diagnosis, and the coding reference lists it alongside more specific variants like I88.0, I88.1, and I88.8. 1 3

Clinical context

Clinical literature describes acute nonspecific mesenteric lymphadenitis as a self-limiting inflammatory condition affecting mesenteric lymph nodes with a presentation that mimics appendicitis or intussusception. 2

Primary nonspecific mesenteric lymphadenitis is defined as right-sided lymphadenopathy without an identifiable underlying inflammatory cause, whereas secondary forms stem from identifiable diseases. 2

What the sources add

While the terminology record limits I88.9 to an unspecified disease label, the clinical article provides operational context by detailing how nonspecific mesenteric lymphadenitis presents and mimics other abdominal conditions. 1 2

The terminology record establishes I88.9 as an active concept with narrower relationships, whereas the coding reference details its exact hierarchical placement among related nonspecific lymphadenitis variants. 1 3

Sources

1. ICD-10-CM I88.9 terminology record — National Cancer Institute Enterprise Vocabulary Services; accessed 2026-07-27.
2. Acute Nonspecific Mesenteric Lymphadenitis: More Than “No Need for Surgery” — pmc.ncbi.nlm.nih.gov; accessed 2026-07-27.
3. I88.9 - Nonspecific lymphadenitis, unspecified | ICD-10-CM — unboundmedicine.com; accessed 2026-07-27.