Immunologic Disorders

IL-10 Receptor Defects

Inheritance: Autosomal recessive
Genes: IL-10RA and IL-10RB
Proteins: IL-10RA and IL-10RB
Tests: IL-10 Receptor Gene Sequencing (IL10RA/IL10RB), IL-10 Receptor Function Screen by Flow

Key Clinical and Laboratory Features

Common clinical features: Severe, early-onset, fistulating inflammatory colitis that is often resistant to therapy. Follicular dermatitis/folliculitis.
Other clinical features: Lymphoma (typically B cell), gingivitis
Physical exam: Severe inflammatory colitis observed by endoscopy. Proctitis is common.
Common laboratory features: Elevated inflammatory markers, leukocytosis

	TEST	COMMENTS
GENE	IL-10 Receptor Gene Sequencing (IL10RA/IL10RB)	The gold standard for confirming a diagnosis of IL-10 receptor deficiency in patients with an abnormal IL-10 Receptor Function Screen.
PROTEIN	N/A	There are currently no available clinical tests to evaluate IL-10RA or IL-10RB protein expression on patient cells.
FUNCTION	IL-10 Receptor Function Screen by Flow	This functional test evaluates the ability of IL-10 to induce tyrosine phosphorylation of STAT3 in patient cells. If the IL-10 receptors are absent or non-functional, no STAT3 phosphorylation is observed. This test is estimated to be at least 90% sensitive to detect patients with defects in one or the other of the IL-10 receptor chains. This test will not identify patients who have IL-10 deficiency.
OTHER		Complete blood count with differential: Leukocytosis can be present.