This case was reported in a literature article and described the occurrence of thrombocytopenia in a 4-year-old female patient who received DTaP vaccine. Co-suspect products included Poliomyelitis vaccine (IPV), MMR vaccine and Varicella vaccine. On an unknown date, the patient received DTaP vaccine at an unknown dose, IPV at an unknown dose, MMR vaccine at an unknown dose and Varicella vaccine at an unknown dose. On an unknown date, an unknown time after receiving DTaP vaccine, the patient experienced thrombocytopenia (serious criteria GSK medically significant), neutropenia (serious criteria GSK medically significant) and lymphadenopathy inguinal. On an unknown date, the outcome of the thrombocytopenia, neutropenia and lymphadenopathy inguinal were unknown. It was unknown if the reporter considered the thrombocytopenia, neutropenia and lymphadenopathy inguinal to be related to DTaP vaccine. Additional information was provided: This case was reported in a literature article and described the occurrence of thrombocytopenia, neutropenia and lymphadenopathy in a 4-year-old female who was vaccinated with unspecified diphtheria tetanus acellular pertussis (DTaP) vaccine, unspecified inactivated polio virus (IPV) vaccine, unspecified measles mumps rubella (MMR) vaccine and unspecified varicella vaccine (manufacturers unknown for all). The patient was a previously healthy girl born at term without complications with a normal newborn screen. No information on patient's medical history or family history or concurrent condition or concomitant medication was provided. On an unspecified date at the age of 4 years, the patient received unspecified DTaP, unspecified IPV, unspecified MMR and unspecified varicella vaccines (administration route and site unspecified; dosages unknown; batch number not provided for all) during her 4 year well child check-up. On an unspecified date, on the same day during her 4 year well child check-up after receiving unspecified DTaP, unspecified IPV, unspecified MMR and unspecified varicella vaccines, the patient was found to have bilateral non tender, non-erythematous inguinal lymphadenopathy. Complete blood count (CBC) showed leukopenia and neutropenia with white blood cells (WBC) at 3900/uL and absolute neutrophil count (ANC) at 83/uL. Platelets were at 29,000/uL. Peripheral smear was negative for blasts. Ultrasound abdomen and pelvis showed inguinal and mesenteric adenitis. Tuberculin test and viral serologies were negative. Follow up physical examinations over the next 6 weeks were positive for generalized lymphadenopathy and persistent cytopenias. Coagulation profile and complement levels were within normal limits (values not provided). Anti-neutrophil antibodies and antinuclear antibodies (ANA) was negative. Antiplatelet antibodies were indeterminate. The patient was referred to the haematology service for thrombocytopenia and new onset bleeding. Bone marrow biopsy was normal. Excisional biopsy of the inguinal lymph node showed follicular hyperplasia without clonal proliferation. Post lymph node biopsy, the patient's platelets dropped to 10,000/uL. Immunoglobulin panel test showed pan hypogammaglobinemia (IgG at 366 mg/dL, IgM at 13 mg/dL, IgA at 18 mg/dL). The patient was treated with intravenous immunoglobulin (IVIG), following which the platelet count increased to 207,000/uL. A diagnosis of common variable immune deficiency (CVID) was made and monthly infusions of IVIG recommended. The patient showed a good response to ITP (Idiopathic Thrombocytopenic purpura) based therapy. The authors did not comment on the causality relationship for thrombocytopenia, neutropenia and lymphadenopathy with unspecified DTaP, unspecified IPV, unspecified MMR and unspecified varicella vaccines. The authors stated that Common variable Immune Deficiency (CVID) is the most common symptomatic autoimmune disorder in children. It presents mostly as recurrent bacterial infections, often associated with cytopenia. However, cytopenia is rarely a presenting symptom. Cytopenias may precede the clinical symptoms of malignant and non-malignant conditions.  Immune deficiencies should be considered as a differential in all such patients.