- Decreased circulating IgM concentration (HP:0002850): An abnormally decreased level of immunoglobulin M (IgM) in blood. Evidence: PCS. Frequency: 1/2. (PMID:15546002)
- Decreased total T cell count (HP:0005403): Abnormal decrease in the absolute number of T cells, commonly characterized as CD3+ lymphocytes, per microliter of blood, compared to a reference range for a given sex and age-group. These may include both TCR alpha/beta and gamma/delta T cells. Evidence: PCS. Frequency: 1/1. (PMID:15546002)
- Abnormal circulating IgG concentration (HP:0410242): An abnormal deviation from normal levels of IgG immunoglobulin in blood. Evidence: PCS. Frequency: 0/2. (PMID:15546002)
- Chronic decreased circulating IgA concentration (HP:0003460): Undetectable serum immunoglobulin A level at a value < 5 mg/dL (0.05 g/L). Evidence: PCS. Frequency: 2/2. (PMID:15546002)
- Infantile onset (HP:0003593): Onset of signs or symptoms of disease between 28 days to one year of life. Evidence: PCS. Frequency: 2/2. (PMID:15546002)
- Recurrent gastroenteritis (HP:0031123): Increased susceptibility to gastroenteritis, an infectious inflammationof the stomach and small intestines manifested by signs and symptoms such as diarheas and abdominal pain, as manifested by recurrent episodes of gastroenteritis. Evidence: TAS. (OMIM:615615)
- Abnormal T cell proliferation (HP:0031379): Any abnormality in the multiplication or reproduction of T cells, which results in the expansion of a cell population. Evidence: PCS. Frequency: 3/3. (PMID:15546002;PMID:8490660)
- Abnormal total B cell count (HP:0010975): The absolute number of B cells in the blood, per microlitre is outside the limits of normal of the reference range for the appropriate sex and age-group. Evidence: PCS. Frequency: 0/2. (PMID:15546002)
- Decreased total CD4+ T cell proportion (HP:0032218): Abnormal decrease of helper CD3+CD4+ T cells, measured as percentage of total CD3+ T cells in the blood, compared to a reference range for a given sex and age-group. These are usually measured within the TCR alpha/beta positive population. Evidence: PCS. Frequency: 1/1. (PMID:8490660)
- Abnormal lymphocyte count (HP:0040088): Any abnormality in the total number of lymphocytes in the blood. Evidence: PCS. Frequency: 1/1. (PMID:8490660)
- Childhood onset (HP:0011463): Onset of disease at the age of between 1 and 5 years. Evidence: PCS. Frequency: 1/1. (PMID:8490660)
- Autosomal recessive inheritance (HP:0000007): A mode of inheritance that is observed for traits related to a gene encoded on one of the autosomes (i.e., the human chromosomes 1-22) in which a trait manifests in individuals with two pathogenic alleles, either homozygotes (two copies of the same mutant allele) or compound heterozygotes (whereby each copy of a gene has a distinct mutant allele). Evidence: TAS. (OMIM:615615)
- Decreased total lymphocyte count (HP:0001888): A reduced number of lymphocytes in the blood. Evidence: PCS. Frequency: 2/2. (PMID:15546002)
- Recurrent otitis media (HP:0000403): Increased susceptibility to otitis media, as manifested by recurrent episodes of otitis media. Evidence: PCS. Frequency: 1/1. (PMID:8490660)
- Recurrent pneumonia (HP:0006532): An increased susceptibility to pneumonia as manifested by a history of recurrent episodes of pneumonia. Evidence: PCS. Frequency: 1/1. (PMID:8490660)
- Recurrent respiratory infections (HP:0002205): An increased susceptibility to respiratory infections as manifested by a history of recurrent respiratory infections. Evidence: TAS. (OMIM:615615)
- Immunodeficiency (HP:0002721): Failure of the immune system to protect the body adequately from infection, due to the absence or insufficiency of some component process or substance. Evidence: PCS. Frequency: 3/3. (PMID:15546002;PMID:8490660)
- Reduced total natural killer cell count (HP:0040218): The absolute count of natural killer cells in the blood, per microlitre, is below the lower limit of normal. Evidence: PCS. Frequency: 0/2. (PMID:15546002)
These phenotypes are associated with the disease immunodeficiency 18 (OMIM:615615).