- Autoimmunity (HP:0002960): The occurrence of an immune reaction against the organism's own cells or tissues. Evidence: PCS. (PMID:22289921)
- Pleural effusion (HP:0002202): The presence of an excessive amount of fluid in the pleural cavity. Evidence: PCS. Frequency: 2/2. (PMID:19425169)
- Persistent EBV viremia (HP:0020072): Persistent or recurrent detection of Epstein-Barr virus (EBV) in the blood that occurs in the context of unusual susceptibility to infection. Evidence: PCS. Frequency: 5/5. (PMID:22289921;PMID:21109689)
- Autoimmune hemolytic anemia (HP:0001890): An autoimmune form of hemolytic anemia. Evidence: PCS. Frequency: 1/2. (PMID:22289921)
- Hepatomegaly (HP:0002240): Abnormally increased size of the liver. Evidence: PCS. Frequency: 2/2. (PMID:19425169)
- 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: 2/2. (PMID:22289921)
- Hemophagocytosis (HP:0012156): Phagocytosis by macrophages of erythrocytes, leukocytes, platelets, and their precursors in bone marrow and other tissues. Evidence: PCS. Frequency: 0/2. (PMID:19425169)
- Recurrent infections (HP:0002719): Increased susceptibility to infections as manifested by repeated bouts of infection. Evidence: PCS. Frequency: 3/3. (PMID:21109689)
- Anemia (HP:0001903): A reduction in erythrocytes volume or hemoglobin concentration. Evidence: PCS. (PMID:19425169)
- Childhood onset (HP:0011463): Onset of disease at the age of between 1 and 5 years. Evidence: PCS. Frequency: 3/3. (PMID:21109689)
- Lymphadenopathy (HP:0002716): Enlargement (swelling) of a lymph node. Evidence: PCS. Frequency: 4/4. (PMID:22289921;PMID:19425169)
- B-cell lymphoma (HP:0012191): A type of lymphoma that originates in B-cells. Evidence: PCS. Frequency: 1/2. (PMID:22289921)
- Splenomegaly (HP:0001744): Abnormal increased size of the spleen. Evidence: PCS. Frequency: 2/2. (PMID:19425169)
- Decreased circulating IgG concentration (HP:0004315): An abnormally decreased level of immunoglobulin G (IgG) in blood. Evidence: PCS. Frequency: 2/3. (PMID:21109689)
- Elevated erythrocyte sedimentation rate (HP:0003565): An increased erythrocyte sedimentation rate (ESR). The ESR is a test that measures the distance that erythrocytes have fallen after one hour in a vertical column of anticoagulated blood under the influence of gravity. The ESR is a nonspecific finding. An elevation may indicate inflammation or may be caused by any condition that elevates fibrinogen. Evidence: PCS. (PMID:19425169)
- Juvenile onset (HP:0003621): Onset of signs or symptoms of disease between the age of 5 and 15 years. Evidence: PCS. Frequency: 4/4. (PMID:22289921;PMID:19425169)
- Decreased circulating immunoglobulin concentration (HP:0004313): An abnormally decreased level of immunoglobulin in blood. Evidence: PCS. Frequency: 2/4. (PMID:22289921;PMID:19425169)
- Lymphoproliferative disorder (HP:0005523). Evidence: PCS. Frequency: 1/2. (PMID:22289921)
- Decreased total leukocyte count (HP:0001882): An abnormal decreased number of leukocytes in the blood. Evidence: PCS. Frequency: 2/2. (PMID:22289921)
- Increased circulating ferritin concentration (HP:0003281): Increased concentration of ferritin in the blood circulation. Evidence: PCS. Frequency: 2/2. (PMID:19425169)
- Elevated circulating C-reactive protein concentration (HP:0011227): The concentration of C-reactive protein in the blood circulation is above the upper limit of normal. Evidence: PCS. Frequency: 2/2. (PMID:19425169)
- Hodgkin lymphoma (HP:0012189): A type of lymphoma characterized microscopically by multinucleated Reed-Sternberg cells. Evidence: PCS. Frequency: 4/5. (PMID:19425169;PMID:21109689)
- Stomatitis (HP:0010280): Stomatitis is an inflammation of the mucous membranes of any of the structures in the mouth. Evidence: PCS. Frequency: 1/2. (PMID:19425169)
- 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: PCS. (PMID:19425169)
- Recurrent fever (HP:0001954): Periodic (episodic or recurrent) bouts of fever. Evidence: PCS. Frequency: 4/4. (PMID:22289921;PMID:19425169)
- Pericardial effusion (HP:0001698): Accumulation of fluid within the pericardium. Evidence: PCS. Frequency: 2/2. (PMID:19425169)
- Autoimmune thrombocytopenia (HP:0001973): The presence of thrombocytopenia in combination with detection of antiplatelet antibodies. Evidence: PCS. Frequency: 1/2. (PMID:22289921)
- Thrombocytopenia (HP:0001873): A reduction in the number of circulating thrombocytes. Evidence: PCS. (PMID:19425169)
- Pancytopenia (HP:0001876): An abnormal reduction in numbers of all blood cell types (red blood cells, white blood cells, and platelets). Evidence: PCS. Frequency: 1/2. (PMID:19425169)
These phenotypes are associated with the disease lymphoproliferative syndrome 1 (OMIM:613011).