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Etymology: Christian Nezelof, French physician, b. 1922
an abnormal condition characterized by absent T cell function, deficient B cell function, fairly normal immunoglobulin levels, and little or no specific antibody production. It affects both male and female siblings, indicating that it may be transmitted as an autosomal-recessive genetic disorder. The cause is unknown. Another theory is that the disorder is caused by underdevelopment of the thymus gland and the consequent inhibition of T cell development. Still another holds that the disease results from a failure to produce or to secrete thymic humoral factors, especially thymosin.
observations Patients with Nezelof's syndrome have progressively severe, recurrent, and eventually fatal infections. Signs that often appear in infants or in children up to 4 years of age include recurrent pneumonia, otitis media, chronic fungal infections, upper respiratory tract infections, diarrhea, and hepatosplenomegaly. The lymph nodes and tonsils may be enlarged, or they may be totally absent in infants with the disease. Involved patients may develop a tendency toward malignancy. Infection may cause sepsis, which is the usual cause of death. Symptoms that often suggest Nezelof's syndrome also include weight loss and poor eating habits. Definite diagnostic evidence of the disease includes defective B cell and T cell immunity despite a normal number of circulating B cells, a moderate-to-high rise in the number of T cells, a deficiency or an increase in one or more classes of immunoglobulins, a nonreactive Schick test after DPT immunization, a reduced or an absent antibody reaction after specific antigen immunization, no thymus shadow on a chest x-ray film, thymus-dependent regions with abnormal lymphoid structure, and a decrease in the number of lymphocytes in the blood.
interventions Initial supportive treatment of Nezelof's syndrome may include monthly injections of gamma globulin or monthly infusions of fresh frozen plasma and heavy use of antibiotics to fight infection. The plasma infusions are especially beneficial if the patient cannot produce specific immunoglobulins. Cell-mediated immune function associated with T cells can usually be temporarily restored within weeks by a fetal thymus transplant. Repeated transplants are required to maintain the immunity. Cell-mediated immunity can be only partially restored with either transfer factor therapy or repeated injection of thymosin. Histocompatible bone marrow transplants have been used, but the effectiveness of this treatment method is unclear.
nursing considerations The nursing role in treating this condition is essentially supportive. Sites of gamma globulin injection in a large muscle mass are massaged after each injection, and the sites are rotated and recorded to prevent tissue damage. Gamma globulin doses greater than 1.5 mL are divided and injected into more than one site. The nurse also offers support to the parents of children affected by Nezelof's syndrome, instructs them how to recognize the signs of infection, and explains the dangers of allowing affected children to become exposed to infection.