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Query: UMLS:C0002895 (sickle cell disease)
 11,747 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Patients with sickle cell disease and individuals who have undergone splenectomy share defects of certain host defense mechanisms and a predisposition to severe pyogenic bacterial infections. Since patients with sickle cell disease can have deficient activity of the alternative complement pathway, we have tested such activity in sera from splenectomized children and adults. A new kinetic hemolytic assay has been used, and we have compared results to those obtained with sera from patients with sickle cell disease or hypogammaglobulinemia. Sera from six of 58 splenectomized individuals (10%) had defective function of the alternative pathway, compared to 10 of 62 sera from patients with sickle cell disease (16%) and 10 of 18 sera from hypogammaglobulinemic patients (56%). Deficiency of antibody, a rate-influencing component of alternative pathway activity in this system, appears responsible for deficient activity in the hypogammaglobulinemic sera. The molecular basis for the deficiency found in sickle cell disease or after splenectomy is not clear. Defective function of the alternative complement pathway could contribute to the increased predisposition to bacterial infection that exists in these three patient groups.
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PMID:Activity of the alternative complement pathway after splenectomy: comparison to activity in sickle cell disease and hypogammaglobulinemia. 38 39

Recurrences of CNS infarction often lead to progressive neurologic disability in sickle cell anemia. To prevent such reccurrence, a periodic blood transfusion program was begun in 1969. Currently, 27 patients are on this regimen. Before inclusion in the program, 12 patients had had one to nine CNS recurrences each. Since the program was started, two patients have had transient CNS ischemia. There were no other recurrences and none of the patients have shown progression of neurologic abnormalities. In addition, there was a striking decrease in bacterial infection and pain. We conclude that periodic transfusions are effective in preventing recurrent CNS infarction in sickle cell anemia. The benefits must be weighed against the potentially serious problem of iron overload, as evidenced by moderately elevated serum ferritin values.
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PMID:Periodic transfusions for sickle cell anemia and CNS infarction. 51 76

One-hundred-and-sixty-six episodes of fever in 162 children with sickle cell anaemia (SCA) aged 6 months to 16 years, presenting to the children emergency room of the University of Benin Teaching Hospital, Nigeria with rectal temperature greater than or equal to 38.3 degrees C were studied for malarial parasitaemia. Non-sicklers of similar ages and with similar temperatures were also studied as controls. Malarial parasitaemia was documented in 9 per cent of children with sickle cell anaemia, and 29 per cent of controls (P less than 0.0001). Bacteraemia occurred in 33 per cent of children with SCA and 26 per cent of controls (P greater than 0.10). Bacteraemia was, therefore, the commonest cause of pyrexia in febrile children with sickle cell anaemia on antimalarial prophylaxis. It is suggested that children with SCA on regular anti-malarial prophylaxis who present with significant pyrexia should be carefully screened for bacterial infection and appropriate anti-microbial therapy instituted.
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PMID:Malarial parasitaemia in febrile children with sickle cell anaemia. 156 41

The pattern of illness in 60 consecutive children with homozygous sickle cell disease who attended the Paediatric Emergency Room of a busy Lagos hospital with acute illness was studied prospectively. Their ages ranged from 3 months to 13 years with a peak in the 2nd year. There were twice as many boys as girls. The commonest symptoms were fever, limb or abdominal pain and cough, and the commonest signs were pallor and hepatomegaly. Painful crises occurred in 27, anaemic crises in 11, and a combination of these in 12 children. Infection was detected in 76% of subjects in crises. Infection was found in 82% of all the children and was mainly bacterial. The commonest infections were pneumonia (35%), bacteraemia (32%), tonsillitis/pharyngitis (17%) and osteomyelitis (8%). The predominant bacteria isolated were Klebsiella spp (38%), E. coli (23%), Staph. aureus (23%), Staph. albus (23%) and Pseudomonas spp (23%). Some children had multiple isolates. Bacterial infection was a major cause of morbidity in very young children and merits appropriate control and preventive measures in this age group. The spectrum of bacteria isolated makes it unlikely that the specific anti-pneumococcal measures widely advocated in Europe and America for young children with SCA would be appropriate in Nigeria.
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PMID:Acute illness in Nigerian children with sickle cell anaemia. 244 66

Osteonecrosis is not well documented as a predisposing factor of septic arthritis despite such a relationship having obvious clinical significance. We report 4 patients with involvement of 5 hips with septic arthritis in established osteonecrotic joints. The etiologies of the osteonecrosis in our study included corticosteroid therapy, sickle cell disease and one case of idiopathic osteonecrosis. Osteonecrosis appears to render the hip more susceptible to hematogenously derived bacterial infection. In some cases, removal of the necrotic tissue may be necessary to cure the infection.
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PMID:Acute septic arthritis in chronic osteonecrosis of the hip. 326 51

Reports in the 1970s suggested that acute chest syndrome (ACS) in children with sickle cell disease is usually due to bacterial infection. Studies in adults and more recently in children, however, showed that proved bacterial infection occurs in a minority of these patients and that vascular occlusion is the main pathologic process. In a retrospective study of 32 episodes of ACS in children, a definite bacterial infection was found in 3% (one patient), possible bacterial infection in 11% (four patients), and a possible mycoplasma in 13% (five patients). With the intent to dilute sickle cells, 23 patients received blood transfusion within 24 hours after hospital admission; all showed a dramatic clinical and roentgenographic improvement. Of the nine patients who did not receive a transfusion after hospital admission, the conditions of five patients deteriorated but improved after "late" transfusion; three patients showed slow improvement, and only one patient improved within 48 hours. From this we conclude that vascular occlusion might be the main process in ACS and that early blood transfusion may be valuable in shortening the course and decreasing mortality. The low hemoglobin value at presentation in our patients makes dilution of sickle cells possible by packed red blood cell transfusion rather than exchange transfusion.
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PMID:Beneficial effect of blood transfusion in children with sickle cell chest syndrome. 334 20

In order to assess the hematologic features of acute bacterial infection in sickle cell anemia, we compared complete blood counts of 23 affected children with proven bacterial infection (Group A) to those of 22 patients with fever but without evidence of bacterial disease (Group B). Univariate and multivariate analyses of the data were carried out. Values for hemoglobin and platelet count were similar in Group A and Group B patients even though these measurements in both groups differed from base line steady state values. Absolute band counts were usually greater in Group A patients, but the sensitivity and specificity of elevated band counts as a diagnostic tool for bacterial infection were relatively low. We conclude that no aspect of the complete blood count can be used to guide major management decisions in febrile children with sickle cell anemia and potentially life-threatening infection.
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PMID:Hematologic alterations during acute infection in children with sickle cell disease. 360 93

Parameters of host defence were investigated in 30 patients with sickle cell disease (SCD). A newly devised perfusion system was used to study the kinetics in whole blood of leucocyte adherence, phagocytosis, killing and solubilization of a mixture of Staph. aureus and Str. pneumoniae, and secretion of lactoferrin. A skin window technique was used to examine the accumulation of leucocytes at inflammatory foci and their subsequent rate of movement through a filter. Serum concentrations of C3, C4, total haemolytic complement and immunoglobulins were also measured. The rate of neutrophil migration into filters was slightly reduced in patients with SCD. The proportion of monocytes that emigrated from the skin windows and their rate of migration were markedly diminished. The adhesion of neutrophils and their ability to kill staphylococci were also reduced, particularly in patients of the haemoglobin (Hb) SS and Hb S-beta-thalassaemia genotypes. Neutrophil function was mostly impaired in patients with the greatest frequency of bacterial infection. The rate of clearance of pneumococci was related to the concentration of type specific immunoglobulin G but not M. Serum concentrations of immunoglobulins and complement were normal. We were unable to define a defect of host defence of sufficient magnitude to explain the susceptibility of these patients to severe infection.
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PMID:Investigations of host defence in patients with sickle cell disease. 388 40

In order to determine the contribution of neutrophil malfunction to the phenomenon of enhanced susceptibility of sickle cell disease patients to bacterial infection, the in-vivo neutrophil migration capacity in 23 sickle cell patients and in 14 normal controls; and the neutrophil reduction of nitroblue tetrazolium dye in 74 sickle cell patients and in 78 normal controls were studied. Secondarily the usefulness of the NBT test in distinguishing between osteomyelitis and uncomplicated bone pain was examined. No impairment of neutrophil migratory capacity was evident as no significant difference was observed between the mean migrated neutrophil count in the sickle cell subjects (1.99 X 10(9)/1) and that in normal controls (2.08 X 10(9)/1). The mean NBT scores were 19.9 +/- 8.9% in non-infected controls and 41.3 +/- 14.6% in infected controls (P less than 0.001). In sickle cell disease they were 23.6 +/- 6% in steady state subjects, 29.2 +/- 16.4% in sterile painful crises, 42.9 +/- 15% in non-osteomyelitic bacterial infection (P less than 0.001) and 18.9 +/- 4.2% during osteomyelitis. Thus all sickle cell subjects apart from those with osteomyelitis showed significant increases in the NBT scores during bacterial infection. The low score in sickle cell osteomyelitis is possibly associated with a relative neutrophil phagocytic defect which requires further elucidation. The NBT test was not useful in distinguishing uncomplicated painful crisis from early osteomyelitis in sickle cell disease.
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PMID:In-vivo neutrophil migration and nitroblue tetrazolium reduction in sickle cell disease. 404 66

Patients with sickle cell anaemia have an increased susceptibility to bacterial infections Previous reports of false-negative nitro blue tetrazolium (NBT) tests in the presence of bacteria infection and of a faulty phagocytic response following stimulation in vitro have suggested the possibility of polymorphonuclear dysfunction in certain patients with sickle cell anaemia. In the present study an unstimulated, histochemical NBT technique was used to evaluate the test in patients with sickle cell anaemia. There was a significant difference between the results in the group of patients with infection (mean NBT-positive cells 42.7%) compared to those without infection (mean 9.4%). There was no significant correlation between the total white blood cell count, absolute number of polymorphonuclear cells, and infectious complications. These findings indicate an appropriate polymorphonuclear cell response, as evaluated by the NBT test, in patients with sickle cell anaemia and bacterial infection. The NBT test may be used as an additional parameter in the differentiation of those patients with sickle cell anaemia with bacterial infection.
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PMID:Sickle cell anaemia and the NBT test. 442 71


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