Evaluation of a prophylactic transfusion program on obstetric outcomes in pregnant women with sickle cell disease: A single centre retrospective cohort study

OBJECTIVE

To evaluate the effects of a prophylactic transfusion program (TP) on obstetric and perinatal outcomes in pregnant women with sickle cell disease (SCD).

METHODS

This retrospective cohort study included all singleton pregnancies among women with SCD in a French university tertiary care center between 1 January 2004 and 31 December 2017. The TP group included patients selected according to the French guidelines who received regular red blood cell transfusions during pregnancy until delivery. The factors associated with TP indication [year of birth, SCD genotype, history of acute chest syndrome and delayed hemolysis transfusion reaction (DHTR) risk score] were taken into account in a propensity score. A composite obstetric adverse outcome was defined associating birth before 34 gestational weeks and/or pre-eclampsia and/or small for gestational age and/or abruption and/or stillbirth and/or maternal death and/or neonatal death.

RESULTS

In total, 246 pregnancies in 173 patients were analyzed. Twenty-two pregnancies with a history of DHTR were excluded. A higher frequency of TP was found before 2013 [119/148 (80.4%) vs 38/76 (50%); p < 0.001]. Rates of preterm birth before 34 gestational weeks (5.6% vs 19.7%; p = 0.001), vaso-occlusive crisis (36.5% vs. 61.8%; p < 0.001), and acute chest syndrome (6.1% vs. 14.5%; p = 0.04) during pregnancy were decreased significantly in the TP group. Among the groups with and without composite obstetric adverse outcomes, the frequency of TP was 52.6% and 74.7%, respectively [odds ratio (OR) 0.30, 95% confidence interval (CI) 0.09-1.02]. The multivariate analysis shows that the TP was associated with a significant reduction in the risk of composite obstetric adverse outcomes (OR 0.28, 95% CI 0.08-0.97; p = 0.04).

CONCLUSION

A red blood cell TP may have an independent protective effect on maternal and perinatal adverse outcomes during pregnancy in women with SCD.

Retinal Photocoagulation for Proliferative Sickle Cell Retinopathy: A Prospective Clinical Trial with New Sea Fan Classification

Purpose

To compare the clinical outcome of stage III proliferative sickle cell retinopathy (PSR) treated by peripheral retinal scatter photocoagulation to natural course disease.

Methods

Long-term follow-up of 101 patients enrolled in a prospective trial of photocoagulation for PSR has been completed. Among 202 eyes of 101 patients enrolled at the University Eye Clinic of Créteil, 73 eyes showed a stage III PSR, which the authors further divided into five new grades (A, B, C, D, E) considering size, hemorrhage, fibrosis, and visible vessels. Grading was based on a three-mirror fundus examination, 360° color photographs, and fluorescein angiography. Mean follow-up was 4 years.

Results

Thirty-eight treated eyes and 35 untreated eyes were included in this study. The evolution was not statistically significant between treated and untreated groups concerning flat sea fan p<1 MPS disc area (grade A) or elevated sea fan with partial fibrosis (grade C). Progression and regression were compared between the two groups for grade B, resulting statistically significant (pp<0.05). Nine complications (13%) were observed, which only occurred in untreated patients with elevated sea fan and hemorrhage (grade B) or complete fibrosed sea fan with well defined vessels (grade E) (pp<0.05).

Conclusions

These data suggest that patients with grade A or C new sea fan classification should not be initially treated but observed.

[Symptomatic extramedullary haematopoiesis in β-thalassemia: A retrospective single centre study]

INTRODUCTION

Symptomatic extramedullary hematopoiesis (EH) is a rare but potentially severe phenomenon which occurs in β-thalassemia. There are no treatment guidelines.

METHODS

Retrospective single centre study including the cases of symptomatic EH encountered between 1997 and 2014 in a unit specialised in red blood cell genetic disorders. Description of clinical, biological and radiological characteristics of the patients, treatments received, and outcomes.

RESULTS

Among 182 β-thalassemia patients followed during the study period, 7 cases of symptomatic EH were diagnosed. They were 5 men and 2 women, and their mean age was 37 years. Four patients were splenectomised, two patients were regularly transfused, and four patients had already received erythropoietin. EH was localised in intravertebral areas and responsible for dorsal spinal cord compression in 5 patients, in paravertebral dorsal area in 1 patient, and in presacral area in 1 patient. The mean hemoglobin level at diagnosis was 7.9 g/dL. Treatment administered included: red cell transfusion in 6 cases, associated with hydroxyurea in 5 cases and/or radiotherapy in 3 patients. One patient was treated with surgery and HU. After a median follow-up of 41 months, clinical recovery was complete in 2 patients and partial in 5 patients.

CONCLUSION

EH must be suspected in β-thalassemia in patients presenting clinical signs of organ compression, and a typical radiological aspect. The functional prognosis depends on the rapidity of treatment, which includes red blood cell transfusion, hydroxyurea, radiotherapy, and rarely surgery. Long-term outcome is uncertain.

Characteristics and outcome of connective tissue diseases in patients with sickle-cell disease: report of 30 cases

OBJECTIVES

To analyze the main characteristics of adults with sickle cell disease (SCD) and concurrent connective tissue disease (CTD).

METHODS

A retrospective investigational study was performed. CTD was diagnosed according to standard international criteria. Severity of SCD was assessed by a clinical severity score.

RESULTS

Thirty patients, 23 women (76%) and 7 men, with hemoglobin S/S (n = 25) or S/C (n = 5) SCD were included. The subtypes of CTD were rheumatoid arthritis (RA) (n = 15), definite systemic lupus erythematosus or "incomplete lupus" requiring treatment (n = 13), primary Sjögren's syndrome with central nervous system involvement (n = 1), and systemic sclerosis (n = 1). Twenty-five of the 30 patients (83%) received steroid treatment, and 15 (50%) received at least 1 immunosuppressive agent (methotrexate in 14 cases) to control CTD. Four RA patients were given antitumor necrosis factor (TNF)alpha and 1 was treated with rituximab without SCD exacerbation. After a median follow-up of 4.5 years [range: 6 months to 30 years] from CTD diagnosis, 11 of the 25 (44%) patients receiving steroids had at least 1 episode of severe infection (mostly due to Staphylococcus aureus or Escherichia coli). SCD exacerbated in 13 of the 30 (43%) patients after CTD onset; 12 of these patients were receiving prednisone and/or methotrexate. Six patients (20%) had died from sepsis (n = 2), stroke (n = 2), or acute chest syndrome (n = 2).

CONCLUSIONS

CTD-related clinical manifestations and outcome were not particularly severe in patients with SCD. However, those with active CTD and undergoing steroid +/- methotrexate treatment had more serious SCD-related manifestations, a higher rate of severe infections, and an overall patient mortality rate of 20%. Thus, the management of patients with CTD and underlying SCD should consider the risk/benefit ratio of each treatment and steroid-sparing strategies should be implemented.

The natural history of asymptomatic osteonecrosis of the femoral head in adults with sickle cell disease

BACKGROUND

Osteonecrosis of the femoral head is a frequent complication in adult patients with sickle cell disease. However, little is known about the natural history of asymptomatic lesions.

METHODS

One hundred and twenty-one patients (121 hips) with sickle cell disease and asymptomatic osteonecrosis of the femoral head that was contralateral to a hip with symptomatic osteonecrosis were identified with magnetic resonance imaging between 1985 and 1995. The lesions were graded with use of the Steinberg classification system. The patients were followed with annual plain radiographs. The mean duration of follow-up was fourteen years.

RESULTS

At the time of the initial evaluation, fifty-six hips were classified as Steinberg stage 0, forty-two hips were classified as Steinberg stage I, and twenty-three hips were classified as Steinberg stage II. At the time of the most recent follow-up, pain had developed in 110 previously asymptomatic hips (91%) and collapse had occurred in ninety-three hips (77%). Symptoms always preceded collapse. Of the fifty-six hips that were classified as Steinberg stage 0 at the time of the initial evaluation, forty-seven (84%) had symptomatic osteonecrosis and thirty-four (61%) had collapse at the time of the most recent follow-up. Of the forty-two asymptomatic stage-I hips, forty (95%) became symptomatic within three years and thirty-six (86%) had collapse of the femoral head. Of the twenty-three asymptomatic stage-II hips, all became symptomatic within two years and all collapsed; the mean interval between the onset of pain and collapse was eleven months. At the time of the final follow-up, ninety-one hips (75%) had intractable pain and required surgery.

CONCLUSIONS

Untreated asymptomatic osteonecrosis of the femoral head in patients with sickle cell disease has a high likelihood of progression to pain and collapse. Because of the high prevalence of complications after total hip arthroplasty in patients with this disease, consideration should be given to early surgical intervention with other procedures in an attempt to retard progression of the disease.

Traitement des arthrites septiques de hanche chez l’adulte drépanocytaire par prothèse totale de hanche

PURPOSE OF THE STUDY

Septic hip arthritis is a recognized complication of sickle-cell disease. The incidence is difficult to assess but is significant since certain authors estimate that 11% of children with sickle-cell disease develop orthopedic complications. We report our experience with hip joint infection in adults with sickle-cell disease.

MATERIAL AND METHODS

We diagnosed ten cases of hip joint infection in seven adults with sickle-cell disease. The characteristic feature of the septic arthritis was the development of a septic focus in a zone of osteonecrosis of the femoral head. Diagnosis was difficult due to the presence of prior hip disease and also the circumstances of development: other infectious foci, septicemia, distant osteomyelitis. The diagnosis was confirmed by joint puncture and isolation of the causal germ. Despite adapted antibiotics and immobilization with traction-suspension, hip joint destruction could not be prevented and all patients became bedridden. Surgery was therefore undertaken to remove the head and neck and institute local antibiotic treatment. A total hip prosthesis was implanted in all patients.

RESULTS

At 2 to 12 years follow-up, all seven patients had nearly normal hip function (all 10 hips). Recurrent infection nevertheless developed in 2 hips, demonstrating the limitations of this technique.

The natural history of symptomatic osteonecrosis in adults with sickle-cell disease

BACKGROUND

Adult patients with sickle-cell disease are at risk for the development of osteonecrosis of the hip. However, there is little information in the literature about the rate of progression of osteonecrosis once symptoms begin. The purpose of this study was to evaluate the natural history of the symptomatic hip in adult patients with osteonecrosis and sickle-cell disease.

METHODS

Ninety-two symptomatic hips in sixty-four consecutive adult patients with sickle-cell disease were initially evaluated between 1980 and 1987. Sixty symptomatic hips had radiographic evidence of osteonecrosis at the initial evaluation: forty-three were classified as stage II; two, as stage III; and fifteen, as stage IV, according to the system of Steinberg et al. The other thirty-two hips had lesions (stage I) that were evident only on magnetic resonance imaging. All patients were evaluated after a mean duration of follow-up of seventeen years.

RESULTS

Of the seventy-five hips without collapse of the femoral head at the initial evaluation, sixty-five demonstrated collapse within five years after the diagnosis. The average time between the diagnosis and collapse was forty-two months for stage-I hips and thirty months for stage-II hips. At the most recent follow-up examination, ninety hips had had collapse of the femoral head and eighty-eight of the ninety-two hips had had surgery because of intractable pain.

CONCLUSIONS

Symptomatic osteonecrosis of the hip in sickle-cell disease has a high likelihood of leading to femoral head collapse, necessitating surgical intervention. When osteonecrosis develops, the deterioration is rapid and, in most patients, operative intervention is necessary because of intractable pain.

LEVEL OF EVIDENCE

Prognostic study, Level II-1 (retrospective study). See Instructions to Authors for a complete description of levels of evidence.

Hb Marseille [α2β2N methionyl - 2 (NA2) His → Pro]: a new β chain variant having an extended N-terminus

A new abnormal hemoglobin was found in a diabetic Maltese woman by citrate agar electrophoresis. This variant was undetectable by isoelectric focusing. No hematological abnormalities were observed. The structural analysis included isolation of the abnormal beta chain, high pressure liquid chromatography of the corresponding tryptic peptides and then microsequencing of the abnormal T1. These procedures revealed a double abnormality: the presence of a methionyl residue extending the NH2 terminus and a histidine to proline substitution in position NA2.

[Physiopathological basis of sickle cell disease, management and current therapeutics]

Physiopathological knowledge in the area of sickle cell disease underwent a first major development three decades ago, some 15 years after the discovery of the molecular nature of the disease. Several physiopathological areas can be distinguished: physiopathology of polymerisation which has been successfully approached by fundamental biophysicists and biochemists alike; physiopathology of the red blood cell; more recently, the characterisation of red blood sickle cells by extra-hemoglobin aspects: the red blood cell is not a passive recipient for hemoglobin but carries out a series of functions which can contribute to physiopathology; the phenomenon of vaso-obstruction is still poorly understood, whereas clinical secondary manifestations of the disease, the physiopathology of infectious risk and severe anaemic manifestations have been well understood. The treatment of sickle cell patients continues to evolve and progress. There are certain characteristics which remain, however, permanent: there is continual interaction between preventive and therapeutic measures; treatment must be both medical and social, given the impact of the disease of the individual and his family or vice-versa; treatment is centred around the hospital with more than ever the necessity to ensure excellence in internal medicine or paediatrics, intensive care and transfusion. Finally, the distinction among three periods for the natural history of the disease remain: before 7 years of age, from 7 years to adult age, adulthood. An integrated, pilot centre for treating patients with sickle cell disease is of crucial importance and can contribute to therapeutic innovations in the area.

[Sickle cell disease: laboratory and hemoglobin study]

The diagnosis of any sickle cell disease syndrome is based on the unambiguous identification of HbS. Electrophoretic tests are usually the first to be performed. A much better resolution is obtained with isoelectricfocusing than with the more conventional cellulose acetate electrophoresis at alkaline pH. In some laboratories the first test is cation exchange HPLC. The diagnosis of HbS should never be accepted if not confirmed by a second test, more specific of this Hb such as the solubility test or electrophoresis on agar in citrate buffer. The laboratory should also evaluate other factors interacting with HbS, such as HbF level, sickle cell restriction haplotype, association with alpha-thalassemias. It should also evaluate other cellular factors and, in case of symptomatic heterozygous patients, help to understand of the underlying mechanisms.

Resveratrol, a natural dietary phytoalexin, possesses similar properties to hydroxyurea towards erythroid differentiation

Resveratrol, a natural dietary polyphenol, has been postulated to be implicated in the cardioprotective effect of red wine and the low incidence of breast and prostate cancers among vegetarians and Orientals respectively. This compound inhibits ribonucleotide reductase as does hydroxyurea, the first therapeutic agent used in the treatment of sickle cell disease. Using the human erythroleukaemic K562 cell line as an in vitro model, we show here that 50 micromol/l of resveratrol induced a higher haemoglobin production (sevenfold) in K562 cells than 500 micromol/l of hydroxyurea (3.5-fold). This erythroid differentiation was linked to a dose- and time-dependent inhibition of cell proliferation associated with an equivalent increased expression of p21 mRNA, but with a higher increased level of p21 protein (sixfold) for cells treated with resveratrol than for those treated with hydroxyurea (1.5-fold). We also show that 50 micromol/l of resveratrol and 25 micromol/l of hydroxyurea induced variable but similar enhancements of fetal haemoglobin synthesis in cultured erythroid progenitors for the majority of the sickle cell patients studied. These inductions were linked to, but not correlated with, a variable decrease in erythroid burst-forming unit clone number. Taken together, these results show that resveratrol merits further investigations in sickle cell disease therapy.

Endothelial dysfunction in patients with sickle cell disease is related to selective impairment of shear stress-mediated vasodilation

Interactions between the endothelium and erythrocytes may contribute to the vascular complications of sickle cell disease (SCD). Endothelium-derived nitric oxide (NO) plays a major role in the regulation of vasomotor tone in response to wall shear stress (WSS) variations and pharmacologic stimuli. However, little is known about endothelial NO production in patients with steady-state SCD. We investigated endothelial NO production in response to flow or vasoactive agonists in 16 homozygous patients with steady-state SCD and 15 controls. Flow-mediated dilation (FMD), arterial diameter changes in response to 100% oxygen inhalation, blood viscosity, and calculated WSS were determined in all patients and controls. At baseline, WSS was higher in SCD patients than in controls, whereas arterial diameter was similar. In patients with SCD, FMD was impaired (1.73% +/- 0.44% vs 3.97% +/- 0.24% in the controls, P <.001) and vasoconstriction in response to 100% oxygen was abolished. Using venous occlusion plethysmography, forearm blood flow (FBF) was evaluated in response to acetylcholine, nitro-monomethyl-L-arginine (L-NMMA), and sodium nitroprusside (SNP) in subgroups of 9 controls and 7 patients with SCD. Acetylcholine induced a significantly greater FBF increase in the patients (9.7 +/- 2.9 mL/min/100 mL of forearm volume vs 2.5 +/- 1.5 mL/min/100 mL in the controls, P <.001), whereas responses to L-NMMA and SNP were similar. These results suggest that endothelial dysfunction may prevent the arterial diameter of patients with SCD from adapting to chronic or acute shear stress elevations. This may contribute to the pathophysiology of vaso-occlusive crisis in patients with SCD.

Frequency of human A gamma 75Thr globin chain in a population from Tunisia

Cord blood samples, collected at Sousse and Monastir, from Tunisian newborns were focused on a thin layer of agarose in order to detect the carriers of the A gamma 75Thr chain (A gamma chain bearing a replacement Ile-->Thr at position 75). Nineteen individuals (10%) were positive for this variant. The frequency of the A gamma 75Thr gene in the Tunisian population (0.050) is compared with that of various ethnic populations.

Acute chest syndrome in adults with sickle cell disease

STUDY OBJECTIVES

Acute chest syndrome (ACS) is a frequent and potentially severe pulmonary illness in sickle cell disease (SCD). The aim of the study was to report the clinical features and outcome of consecutive ACS episodes in adult patients in a French SCD center. All patients were treated according to an uniform therapeutic protocol applying transfusion only in the more severe clinical form of ACS.

RESULTS

There were 107 consecutive episodes in 77 adult patients (mean age, 29 +/- 7 years; 78% hemoglobin [Hb] SS; 14% Hb SC; and 8% Hb Sbeta + thalassemia) over a 6-year period. Seventy-eight percent of our patients had an associated vaso-occlusive crisis that preceded the chest signs in half of the cases. Comparison between acute and baseline levels showed a statistically significant difference in Hb levels (drop of 1.6 to 2. 25 g/dL depending on Hb genotype), WBC count (increase of 9.2 +/- 8. 3 x 10(9)/L); platelet count (increase of 67 +/- 209 x 10(9)/L); and lactate dehydrogenase values (increase of 358 +/- 775 IU/L) in ACS patients. Hypercapnia was detected in 42% of patients without sign of narcotic abuse. We identified a high percentage of alveolar macrophages containing fat droplets in 31 of 43 (77%) patients who underwent BAL. Bacterial culture findings were almost always negative, but were performed after starting antibiotic therapy that was administered in 96 episodes. Transfusion was required in 50 of 107 ACS events (47%). Five patients died, and all were transfused.

CONCLUSIONS

These results confirm that fat embolism is probably a frequent mechanism of ACS in adult patients. However, fat embolism was not associated with a more severe clinical course, suggesting that bronchoscopy and BAL have little impact on the management of these patients. Restricting transfusion to the most severe ACS cases does not seem to increase the mortality rate.

Oral magnesium pidolate: effects of long-term administration in patients with sickle cell disease

Prevention of erythrocyte dehydration by specific blockade of the transport pathways promoting loss of potassium (K) is a potential therapeutic strategy for sickle cell (SS) disease. Dietary magnesium (Mg) pidolate supplementation over a 4-week period has been shown to inhibit K-Cl co-transport and reduce dehydration. We report here the results in 17 of 20 patients with SS disease treated in an open-label unblinded study of the effects of long-term (6 months) oral Mg pidolate administration (540 mg Mg/d). A significant decrease (P < 0.0025) was observed with Mg therapy in the distribution widths for red cell mean cell haemoglobin concentration (MCHC) (haemoglobin distribution width; HDW), reticulocyte mean cell volume (red cell distribution width of reticulocytes; RDWr) and MCHC (reticulocyte HDW; HDWr), activity of red cell K-Cl co-transport, Na/Mg exchanger and Ca2+-activated (Gardos) K+ channel, whereas red cell K and Mg contents were significantly increased. Hb levels and absolute reticulocyte counts did not change with Mg therapy. Two patients did not complete the trial because of diarrhoea and one did not complete the trial for unrelated reasons. Although the median number of painful days in a 6-month period decreased from 15 (range 0-60) in the year before the trial to 1 (range 0-18; P < 0.0005) during the period of Mg therapy, no firm conclusion on therapeutic efficacy could be drawn from this unblinded open-label trial.

Pulmonary function in sickle cell disease with or without acute chest syndrome

Recurrent acute chest syndrome (ACS) has been suggested as a risk factor for chronic lung dysfunction in sickle cell disease. To investigate this hypothesis, lung function tests were performed in 49 sickle cell disease outpatients whose condition was stable, including 23 patients with a history of two to four episodes of ACS (ACS+) and 26 with no history of ACS (ACS-). The two groups were comparable regarding the sex ratio, body mass index, smoking history, physical characteristics, clinical history and usual lung function tests. Respiratory resistance (Rrs), measured using the forced oscillation technique, increased with the number of ACS episodes (r=0.55, p<0.0001) and a significant relationship was observed between Rrs as an independent variable and the expiratory flow rates at 25, 50 and 25-75% of the forced vital capacity as explanatory variables (r= 0.36, p<0.02; r=0.35, p<0.02; and r=0.4, p<0.006, respectively), with higher Rrs being associated with lower expiratory flow rates. The transfer factor (TL,CO) and transfer coefficient (KCO) for CO were significantly higher in the ACS+ group than in the ACS-group (TL,CO=84+/-4 versus 71+/-3%, p<0.004 and KCO=102+/-5 versus 90+/-3%, p<0.05, respectively). The data demonstrate that obstructive lung dysfunction is fairly common in sickle cell disease and suggest that recurrent acute chest syndrome may contribute specific obstructive defects. The increase in respiratory resistance associated with acute chest syndrome was accompanied by an increase in diffusion capacity, suggesting that it may have been related to an increase in lung blood volume.

Hemoglobins in Togolese newborns: Hb S, Hb C, Hb Bart's, and alpha-globin gene status

The gene frequency of the most important hemoglobin (Hb) abnormalities is reported in a population of 171 Togolese newborns. Hb phenotypes, hematological parameters, and the more frequently described alpha-gene deletions were analyzed. Structural abnormalities of beta-globin were observed in 35.7% of the children with a gene frequency of 0.105 for beta(S) and 0.091 for beta(C). The frequency of the different alpha-globin genotypes was alpha alpha/ = 0.71, -alpha/ = 0.28, and alpha alpha alpha/ = 0.01. All of the individuals homozygous for the -alpha genotypes, and most of the heterozygous individuals, carried Hb Bart's. Within the alpha alpha/alpha alpha and the -alpha/alpha alpha groups, several individuals with or without Hb Bart's were found; they did not differ from the others by their red blood cell (RBC) parameters but by their levels of fetal hemoglobin (Hb F). The African alpha2 polymorphism marker, characterized by the replacement of G by TCGGCCC at position 7238 (EMBL HSHBA4, 1993) and of T 7174 by G, was found in 21 newborns. The mean value of Hb F was calculated for each genotype, the mean (G)gamma percentage was 69.4 +/- 4.0%, and the gene frequency of the AgammaT marker was 0.10; this marker was linked to the normal beta-globin cluster.

Early glomerular dysfunction in patients with sickle cell anemia

The purpose of this study was to analyze the determinants of glomerular filtration in nonnephrotic young adult patients with sickle cell anemia (SCA). We prospectively screened 14 patients with homozygous SCA who had normal plasma creatinine concentrations and normal or moderately elevated albuminuria (< 1 g/d). Inulin, paraaminohippuric acid, and dextran clearances were evaluated and compared with values obtained from a control group (age-matched healthy volunteers). SCA patients had a significantly higher glomerular filtration rate and effective renal plasma flow than controls (146 +/- 9 mL/min/1.73 m2 v 120 +/- 3 mL/min/1.73 m2 [P < 0.01] and 1,052 +/- 69 mL/min/1.73 m2 v 709 +/- 38 mL/min/1.73 m2 [P < 0.001], respectively). We found no correlation between glomerular filtration rate or effective renal plasma flow and hematocrit. Fractional clearance of neutral dextran was significantly elevated in SCA patients for all radii between 3.4 and 5.4 nm. Theoretical analysis of dextran transport through a heteroporous membrane model revealed a slight increase in the mean radius (ro) of restrictive pores (5.68 nm v5.50 nm; P < .001) and no significant difference in shunt pathway (omega o) values. Among the other hemodynamic parameters, the most significant change was a dramatic increase in ultrafiltration coefficient (41.3 +/- 3.6 mL/mm Hg/min/1.73 m2 v 25.1 +/- 2.6 mL/mm Hg/min/1.73 m2; P < 0.001). Our results suggest that hyperfiltration in SCA patients is associated not only with enhanced renal perfusion but also with an alteration in glomerular permeability and with an increase in Kf. This change in Kf is fully in agreement with the large increase in glomerular area previously described in SCA patients. Based on our results and those of previous morphologic studies, we propose that enhanced transglomerular trafficking of macromolecules associated with podocyte stretch lesions (defects) induced by glomerular hypertrophy may play a role in the genesis of this particular form of focal segmental glomerulosclerosis, which is associated with SCA.

Abnormalities of the adult shoulder due to sickle cell osteonecrosis during childhood

PATIENTS AND METHODS

A retrospective study of 110 adults with sickle cell anemia (SS genotype) was conducted to determine the frequency of complications of sickle cell osteonecrosis of the shoulder in childhood. The glenohumeral joint was evaluated on plain anteroposterior and lateral radiographs of the shoulder.

RESULTS

Mean time since osteonecrosis of the shoulder was 24 years. Radiographic abnormalities were seen in 106 of the 220 shoulders (48.2%). Both shoulders were affected in 86% of cases and at least one hip in 96%. Radiographic abnormalities included isolated caput magna, caput plana, a short humeral neck and ascension of the tuberosities. Twelve shoulders exhibited glenoid fossa abnormalities, which consisted in complete or partial hypoplasia. Evidence of glenohumeral osteoarthritis was seen in 11 shoulders.

DISCUSSION

The shoulder abnormalities seen in our patients were probably due to growth disturbances in the proximal humerus secondary to osteonecrosis of the humeral head during childhood. They were common but less likely to produce functional impairment than osteonecrosis-related lesions of the hip. However, some patients had premature osteoarthritis and geometric shoulder abnormalities responsible for functional loss in adulthood.