ABSTRACT
BACKGROUND: Pulmonary hypertension (PHTN) is a potentially life-threatening complication, detected by echocardiographic evidence of elevated tricuspid regurgitant velocity (TRV). This condition has been described in adults with sickle cell disease (SCD) and other hemolytic disorders; however, there is little information on the occurrence of this condition in pediatric patients. METHODS: Records for pediatric SCD patients were retrospectively reviewed to determine clinical characteristics and co-morbidities of patients with elevated TRV on echocardiograms obtained under steady state conditions as an outpatient. Correlation of TRV > or =2.5 m/sec with age, sex, type of SCD, number of outpatient echocardiograms per patient, episodes of vasoocclusive crisis (VOC) and acute chest syndrome (ACS), mean hemoglobin and reticulocyte count, asthma, obstructive sleep apnea, cerebrovascular disease (CVD), and hydroxyurea therapy was determined. RESULTS: Of 224 SCD patients, 44 had outpatient echocardiographic measurement of TRV. Patients (11 of 44) (26.2%) with TRV > or =2.5 m/sec were compared to 31 patients without elevated TRV. Significant differences were noted for percent with HbSS disease (P = 0.041), CVD (P = 0.021), hemoglobin (P = 0.003), % reticulocytes (P = 0.037), and number of echocardiograms performed (P < 0.001). No significant differences were observed for gender, age, asthma, or frequency of VOC and ACS. CONCLUSIONS: Elevated TRV, a surrogate marker for PHTN, occurs in children with SCD and is associated with low hemoglobin, elevated reticulocyte count, and cerebral vasculopathy. Appropriate screening by echocardiography can lead to detection and treatment that may reduce TRV and potentially reverse the disease process, prevent the increased morbidity and mortality associated with PHTN.
Subject(s)
Anemia, Sickle Cell/complications , Hypertension, Pulmonary/diagnosis , Tricuspid Valve Insufficiency/physiopathology , Adolescent , Adult , Anemia, Sickle Cell/physiopathology , Child , Child, Preschool , Echocardiography , Female , Humans , Hypertension, Pulmonary/etiology , Hypertension, Pulmonary/physiopathology , Infant , Infant, Newborn , Male , Pulmonary Artery/physiopathology , Retrospective StudiesABSTRACT
Hepatitis B surface antibody titers were routinely measured in 150 children with sickle cell disease (SCD) after immunization, and the seroconversion rate was found to be lower than that in the general population (89% vs. 97%, P = 0.002). Most of the children who did not seroconvert after the series of 3 immunizations responded to booster injections (93%). Therefore, we recommend the measurement of hepatitis B surface antibody titers after immunization in those children with SCD at greatest risk for hepatitis B infection. An additional dose of hepatitis B vaccine should be administered to those without evidence of seroconversion.
Subject(s)
Anemia, Sickle Cell/immunology , Hepatitis B Antibodies/blood , Hepatitis B Surface Antigens/immunology , Hepatitis B Vaccines/immunology , Anemia, Sickle Cell/physiopathology , Child , Child, Preschool , Female , Humans , Male , VaccinationABSTRACT
The purpose of this study was to determine the age-related risks, disease-specific risks, and characteristics of serious pneumococcal infections in children with sickle cell disease (SCD) while penicillin prophylaxis was standard. The clinical experiences of three pediatric sickle cell programs spanning January 1, 1992, to May 31, 1998, were combined. Data were collected regarding the patients followed up and the characteristics of bacteremia and meningitis cases. Forty-seven pneumococcal infections (44 bacteremia, 3 meningitis) among 40 patients with SCD were observed. Forty infections occurred in children with homozygous hemoglobin S (SS) during 4108 patient-years at a median age of 22 months; 7 occurred in double heterozygous hemoglobin SC (SC) children during 1777 patient-years at a median age of 23 months. Ten infections occurred among 9 SS children 5 years or older. Most children in whom infections developed were reportedly taking prophylactic penicillin and when older than 24 months old had received Pneumovax (Merck & Co., Inc., West Point, PA, U.S.A. The following pneumococcal serotypes were identified in 15 cases studied: 6A, 6B, 9V, 14, 15B, 18B, 18F, 19F, and 23F. Infections resulted in five deaths and two strokes. The observed severe pneumococcal infection rate in SS children younger than 5 years was less than that reported before penicillin prophylaxis, supporting routine penicillin prophylaxis in this specific population. The optimal duration of penicillin prophylaxis in older children with SCD remains unknown. The administration of 7-valent Prevnar (Wyeth Lederle Vaccines, Philadelphia, PA, U.S.A.) to children younger than 24 months old with SCD should be beneficial, based on the serotype data.
