D3.348 - A Case of 19p13.3 Microdeletion
Case report
Introduction
19p13.3 Microdeletion is a scarce genetic condition. It has been reported to present with facial dysmorphism, developmental delay, intellectual disability, and speech impairment (1,2).
Case
A 16-year-old male was referred to us for immunological evaluation due to stunted growth and recurring pulmonary infections. A perusal of the patient's medical history revealed the following information: he was born by cesarean section at 39 weeks and 3000g; he underwent surgery for undescended testicles at the age of 6 months; he began walking at the age of 4 years; there was no consanguinity between his parents; his father was mentally retarded after meningitis; and his two sisters died at the age of 14 days (the cause of death is unknown). The patient was hospitalized with mental retardation, delayed fine motor skills, recurrent monoliasis, and pneumonia. A thorough examination of body weight was 27kg (<3p, SDS:-7.1), height:148cm (<3p, SDS:-4). Hypopigmented, erythematous, squamous, pruritic skin lesions were observed on the neck and elbows. The patient's dysmorphic findings were as follows: a syndromic face, small ears, hypertelorism, an anteriorly positioned lower jaw, eyebrows that were externally spilled (Hertoghe sign), and small hands and feet. Lab tests showed a normal complete blood count, low IgG and IgM levels, and IgA and IgE levels for age. Lymphocyte analysis detected low memory B, switched B and NK cells, and increased activated T cells. Immunoglobulin replacement therapy was initiated intravenously, and further investigative procedures were scheduled. A microarray comparative genomic hybridization identified a 1.082 kilobase single copy deletion in the 19p13.3 region.
Conclusion
The signs and symptoms of 13 deletion syndrome come from the loss of multiple genes. Microdeletions (0.2-3.6 Mb) vary in size, so 5-100 genes may be missing. Examples of these genes are GIPC3, THEG, SHC2, ELANE, STK11, KISS1R, ACTAY, GNA11, TLE2, TBXA2R, PIP5K1C, RAX2, EEF2, ZBTB7A, MAP2K2, CREB3L3, SH3GL1, SEMA6B. Concerning immunity, the ELANE gene causes congenital neutropenia, and the ARID3A gene regulates B cells and is critical for developmental plasticity (3). Patients with neuromotor developmental retardation and frequent illnesses should undergo comprehensive immunological examination.
