A Novel BLNK Gene Mutation in a Four-Year-Old Child Who Presented with Late Onset of Severe Infections and High IgM Levels and Diagnosed and Followed as X-Linked Agammaglobulinemia for Two Years

Table 2

Reported patients with BLNK protein deficiency.

Patient (reference)	Age at onset (years), gender, ethnicity	Infection profile	Additional manifestations	Ig levels at diagnosis (mg/dL)	Circulating CD19^+ B cells (%)	BLNK; Mutation
Patient 1 (Minegishi et al. [5])	8 months,; male, Caucasian of Scot/Irish ancestry	Recurrent otitis and pneumonia; hepatitis C	Intermittent protein losing enteropathy	Undetectable	0.05	Homozygous; c.30°C > A (p.P10P)/c.47 + 3 A > T
Patient 2 (Conley et al. [2])	8, female, Turkish	Recurrent respiratory infections, diarrhea, otitis, septic arthritis, and conjunctivitis	Resolved hepatitis with no clear diagnosis	IgG 111; IgA < 6; IgM 10	0.01	Homozygous c.367 C > T (p.R123X)
Patient 3 (Lagresle-Peyrou et al. [9])	6, male, NA	Recurrent otitis and pneumonia	None	Undetectable	0	Homozygous; c.844 C > T (p.R282X)
Patient 4 (NaserEddin et al. [8])	0.5, male, Arab	Recurrent otitis media, chronic diarrhea, enteroviral viremia	Chronic polyarthritis, dermatitis and sensorineural hearing loss	Undetectable	0	Homozygous c.435_436 del T CInsA (p.E145fs25)
Patient 5 (NaserEddin et al. [8])	1, female (elder sister of P4), Arab	Recurrent diarrhea, otitis media and sino-pulmonary infections	Arthritis, bronchiectasis	Undetectable	0	Homozygous c.435_436 del T CInsA (p.E145fs25)
Patient 6 (Geier et al. [10])	28, male, Turkish	No increased susceptibility to infections	Chronic renal insufficiency	IgG 903; IgA 791; IgM 27 (selective IgM deficiency)	14	Compound heterozygous c328 C > G (pPro110Ala)/c472 G > T (pAla158Ser)
Patient 7 (Niu Li et al. [11])	5, female, Chinese	Respiratory infections, including sinusitis, bronchitis, and pneumonia	Epilepsy, allergic rhinitis and wheezing	IgG 135; IgA < 6; IgM < 18	3.5	Compound heterozygous c.676 + 1 G > A, exon 9 deletion, c.677_746del, p.R227Kfs  7
Patient 8 (Niu Li et al. [11])	2, male, Chinese	Recurrent bronchitis, pneumonia, and acute lymphadenitis	None	Undetectable	3	Heterozygous frameshift variant c.452_453dup CC, (p.T152Pfs  6), c. 525G > A
Patient 9 (our presented case)	3.5, male, Turkish	Recurrent respiratory tract	None	IgG 81; IgA < 5; IgM 258	0,05	Homozygous mutation c.790 C > T (p.Gln264Ter)