Primary immunodeficiency or monogenic inflammatory bowel disease

Gene: TLN1

Red List (low evidence)

PMID:35861643 reported a 20-year old man of Mexican ancestry with a complex phenotype including thrombocytopenia, T lymphopenia, and low IgG levels. The patient had an absolute lymphocyte count of <1000/mcL and low absolute T-cells. Recent B-cell subset analysis revealed 96% naïve and 4% switched memory B-cells and initial serum immunoglobulin levels at six years of age included: IgG 273, IgA 130, IgM 36. Because of poor antibody responses to pneumococcal vaccine, he was started on immunoglobulin replacement therapy, which he has continued to the present.

He continued to experienced intermittent sinusitis, otitis media and bronchitis since 10 years of age, which cleared with oral antibiotics. At 18 years of age, he had abdominal pain at times that was diagnosed as small intestinal bacterial overgrowth, headaches often treated as migraines, and joint pain with limited signs of active arthritis.

He was identified with a de novo heterozygous variant c.685C > T (p.Pro 229 Ser) that was not present in his parents.
Sources: Literature

Created: 3 Mar 2023, 7:38 a.m. | Last Modified: 3 Mar 2023, 7:46 a.m.

Panel Version: 3.6

Mode of inheritance
MONOALLELIC, autosomal or pseudoautosomal, imprinted status unknown

Phenotypes
lymphopenia, MONDO:0003783

Publications

• 35861643