Hematological parameters in sickle cell anemia patients with and without priapism

Pathophysiological characterization of the Townes mouse model for sickle cell disease

A deeper pathophysiologic understanding of available mouse models of sickle cell disease (SCD), such as the Townes model, will help improve preclinical studies. We evaluated groups of Townes mice expressing either normal adult human hemoglobin (HbA), sickle cell trait (HbAS), or SCD (HbS), comparing younger versus older adults, and females versus males. We obtained hematologic parameters in steady-state and hypoxic conditions and evaluated metabolic markers and cytokines from serum. Kidney function was evaluated by measuring the urine protein/creatinine ratio and urine osmolality. In vivo studies included von Frey assay, non-invasive plethysmography, and echocardiography. Histopathological evaluations were performed in lung, liver, spleen, and kidney tissues. HbS mice displayed elevated hemolysis markers and white blood cell counts, with some increases more pronounced in older adults. After extended in vivo hypoxia, hemoglobin, platelet counts, and white blood cell counts decreased significantly in HbS mice, whereas they remained stable in HbA mice. Cytokine analyses showed increased TNF-alpha in HbS mice. Kidney function assays revealed worsened kidney function in HbS mice. The von Frey assay showed a lower threshold to response in the HbS mice than controls, with more noticeable differences in males. Echocardiography in HbS mice suggested left ventricular hypertrophy and dilatation. Plethysmography suggested obstructive lung disease and inflammatory changes in HbS mice. Histopathological studies showed vascular congestion, increased iron deposition, and disruption of normal tissue architecture in HbS mice. These data correlate with clinical manifestations in SCD patients and highlight analyses and groups to be included in preclinical therapeutic studies.

Platelet volume parameters as a tool in the evaluation of acute ischemic priapism in patients with sickle cell anemia

OBJECTIVE

This study aimed to evaluate the predictive value of platelet volume indices (PVIs), such as mean platelet volume (MPV), platelet distribution width (PDW), and plateletcrit (PCT), as prognostic parameters of detumescence in acute ischemic priapism (IP) patients with sickle cell anemia (SCA) in steady-state who received intracavernosal injections of phenylephrine with aspiration and saline irrigation.

METHODS

Fifty-six SCA patients with acute IP and 54 healthy male control subjects were included in the research. Priapism was diagnosed by penile Doppler ultrasound and corporal blood gas tests before intervention. Measurements of PVIs (MPV, PDW, and PCT) and TLC were ordered for all participants. Additionally, the duration of priapism was recorded. The area under the curves was calculated by receiver operating characteristic (ROC) regression analysis.

RESULTS

The detumescence rate was 71.4% after the intervention. Compared to the control group, priapic SCA patients showed significantly higher PLT (p = 0.011), MPV (p = 0.002), PDW (p = 0.032), PCT values (p = 0.022), and TLC (p = 0.027). Higher MPV, PDW, and PCT values were observed in unsuccessful detumescence patients compared to the resolution group (p < 0.05). Statistically significant cutoff values for persistent priapism were measured by ROC as PLT: ⩾ 254x103/μL; MPV: ⩾ 13.2 fL; PDW: ⩾ 15.6 fL; PCT: ⩾ 24%; and TLC ≥ 8.5x103/L. Priapism duration of ≤ 17.9 hours was significantly related to detumescence rate (p = 0.000). Multivariable logistic regression analysis showed that priapism duration and higher MPV are prognostic parameters for detumescence in SCA.

CONCLUSIONS

The higher MPV and duration of priapism can be used as parameters for evaluating detumescence outcomes in steady-state SCA with acute IP.

Priapism in sickle cell disease: Associations between NOS3 and EDN1 genetic polymorphisms and laboratory biomarkers

Priapism is a urologic emergency characterized by an uncontrolled, persistent and painful erection in the absence of sexual stimulation, which can lead to penile fibrosis and impotence. It is highly frequent in sickle cell disease (SCD) associated with hemolytic episodes. Our aim was to investigate molecules that may participate in the regulation of vascular tone. Eighty eight individuals with SCD were included, of whom thirty-seven reported a history of priapism. Priapism was found to be associated with alterations in laboratory biomarkers, as well as lower levels of HbF. Patients with sickle cell anemia using hydroxyurea and those who received blood products seemed to be less affected by priapism. Multivariate analysis suggested that low HbF and NOm were independently associated with priapism. The frequency of polymorphisms in genes NOS3 and EDN1 was not statistically significant between the studied groups, and the presence of the variant allele was not associated with alterations in NOm and ET-1 levels in patients with SCD. The presence of the variant allele in the polymorphisms investigated did not reveal any influence on the occurrence priapism. Future studies involving larger samples, as well as investigations including patients in priapism crisis, could contribute to an enhanced understanding of the development of priapism in SCD.

Clinical and laboratory parameters, risk factors predisposing to the development of priapism in sickle cell patients

Although sickle cell disease is very common in Oman, priapism is a relatively rare complication of this disease. This study was aimed to identify the clinical and laboratory risk factors that predispose sickle cell disease patients to priapism. In a retrospective, case-control study, data on 21 male sickle cell disease patients, with priapism, were compared to 20 age and sex-matched sickle cell disease patients without priapism from the hospital medical records. Specifically, the demographical, hematological, biochemical, and clinical parameters including complications attributable to priapism were studied. Means for continuous measures and independent t-test were used to evaluate the association between the parameter studied and the occurrence of priapism. Priapism occurrence was associated with low basal hemoglobin (Hb), along with an increase in other parameters such as white blood cell count (WBC) ( P = 0.010), platelet count ( P = 0.001), reticulocyte count ( P < 0.001), mean corpuscular volume (MCV) ( P < 0.001), and mean corpuscular hemoglobin (MCH) ( P < 0.001). Biochemical laboratory parameters revealed an association with an increased total bilirubin ( P < 0.001). Patients with priapism were more likely to have acute chest syndrome, stroke, pulmonary hypertension, asplenia ( P = 0.006), gallbladder stones, and consequently cholecystectomy. Blood exchange and Penile aspiration were the most frequent medical therapies ( P = 0.010 and P < 0.001 respectively). Patients with sickle cell disease who presented with priapism were young adults with low Hb, high WBC’s, platelets, reticulocytes, MCV, MCH, bilirubin, and LDH. These findings suggest an association of priapism with increased hemolysis.

Impact statement

Sickle cell disease is prevalent throughout the world with a 5.8% incidence of sickle cell trait among the Omani population, yet priapism was a relatively rare complication. Penile erection and detumescence are complex physiological processes, which require a delicate neurohormonal and cardiovascular response. In this cohort, young SCD patients developed priapism with a low incidence of complications. These patients had high WBCs, platelets, bilirubin, LDH, and reticulocytes with low hemoglobin as compared to controls, suggesting an increased hemolytic process. Favorable outcome was dependent on early intervention, with almost half of these patients needing surgical intervention.

Hematological parameters in Ghanaian sickle cell disease patients

BACKGROUND

Effective treatment and management of sickle cell disease (SCD) has been a challenge in Africa over the years. Hematological parameters are very useful profiles in the effective management of the disease. However, there is scarcity of studies on the hematological parameters of SCD in Ghana. This study aimed at determining hematological parameters among SCD patients with vaso-occlusion, those in the steady state as well as healthy controls at a teaching hospital in Ghana.

METHODOLOGY

This was a cross-sectional study involving a total of 628 subjects, including 148 HbAA controls, 208 HbSS patients in steady state, 82 HbSC patients in steady state, 156 HbSS patients in vaso-occlusive crises (VOC), and 34 HbSC patients in VOC. Venous blood sample was collected from all study participants. A full blood count was done within 2 hours of collection, and hemoglobin (Hb) concentration, packed cell volume, red blood cell (RBC) concentration, mean corpuscular Hb, mean cell volume, mean corpuscular Hb concentration, and white blood cells (WBC) and platelet (PLT) counts were recorded.

RESULTS

WBC and PLT counts were significantly higher in both female and male patients with SCD, compared with their healthy counterparts (P<0.05). The level of WBC was, however, significantly higher in patients with HbSS VOC among the SCD patients (P<0.001). Levels of Hb, RBC, and hematocrit were significantly higher in the controls (P<0.001). There was no significant difference in mean cell Hb among male patients with SCD (P=0.274) and female patients with SCD (P=0.5410).

CONCLUSION

The SCD patients had lower Hb and RBC than the controls; however, higher PLT and WBC are noted in various status of SCD, possibly reflecting spleen effect in these patients. Further studies are needed to confirm these findings.

Thyroid Function in Egyptian Children with Sickle Cell Anemia in Correlation with Iron Load

BACKGROUND

Sickle Cell Disease (SCD) is characterized by defective hemoglobin synthesis, hemolytic anemia, frequent thrombosis and chronic organ damage including endocrine organs.

AIM

To assess thyroid function in children with SCD in correlation and iron load.

PATIENTS AND METHOD

This study was conducted on 40 children with SCD with iron overload (serum ferritin more than 1000 ng/ml) including 22 males and 18 females with their ages ranging from 11-14 years and mean age value of 11.63±1.36 years and 40 healthy children of matched age and sex as a control group. For all patients; complete blood count, hemoglobin electrophoresis, serum ferritin, serum iron, iron binding capacity and thyroid function including Free Thyroxine (FT4), Free Triiodothyronine (FT3), Thyroid Stimulating Hormone (TSH), Thyroid Peroxidase Antibody (TPOAb) and Thyroglobulin Antibody (TgAb) were done.

RESULTS

Significantly higher serum ferritin and iron and significantly lower Total Iron Binding Capacity (TIBC) were found in patients compared with controls (mean serum ferritin was 1665.2±1387.65ng/ml in patients versus 192.55±107.2ng/ml in controls with p-value of 0. 007, mean serum iron was 164±83.9 ug/dl in patients versus 89.5±4.5ug/dl in controls with p-value of 0.039, mean TIBC was 238±44.5ug/dl in patients versus 308±11ug/dl in controls with p-value of 0.001). Significantly higher serum TSH and significantly lower Free T3 and Free T4 were found in patients compared with controls with no significant correlation between thyroid hormones and serum ferritin (mean serum TSH was 4.61±1.2 µIU/mL in patients versus 2.11 ± 0.54 µIU /mL in controls with p-value of 0. 045, mean serum FT3 was 2.61 ±1.3 pg/mL versus 3.93±0.47pg/mL in controls with p-value of 0.027, mean serum FT4 was 0.91±0.174 ng/dL versus 1.44± 0.164 ng/dLin controls with p-value of 0.047, r = - 0. 008 and p-value was 0. 973 for correlation between free T4 and serum ferritin, r = -0. 028 and p-value was 0. 9 for correlation between TSH and serum ferritin and r= - 0.259 and p-value was 0.27 for correlation betweenT3 and serum ferritin). There were no significant differences between patients and controls regarding thyroid peroxidase antibody and thyroglobulin antibody (mean serum thyroid peroxidase antibody was 22.45± 4.32 in patients versus 22.45 ± 3.21 in controls with p-value of 0.98 while mean serum thyroglobulin antibody was 12.32 ± 2.65 in patients versus 12.99 ± 2.34 in controls with p-value of 0.76.

CONCLUSION

Thyroid hormones deficiency may occur in some patients with SCD.

RECOMMENDATIONS

Regular assessment of thyroid function in children with SCD may be recommended as they are more vulnerable to develop hypothyroidism and may require replacement therapy.

Red blood cell deformability is reduced in homozygous sickle cell disease patients with leg ulcers

Previous reports differ as to whether a decreased elongation index (EI), a proxy for red blood cell (RBC) deformability, is associated with leg ulcers (LU) in people with homozygous sickle cell disease (SCD). We sought to determine whether erythrocyte deformability (ED) and haematological indices were associated with the presence of LU in patients with SCD. The study design was cross-sectional. Twenty-seven patients with LU and 23 with no history of ulceration were recruited into the study. A laser assisted rotational red cell analyzer was used in the determination of the EI. Haematological indices were determined using a CELL-DYN Ruby haematology analyzer. Data were normally distributed and presented as means±SD. Two-sample t-test was used to test for associations between haemorheological variables in SCD patients with and without LU. Statistical significance was taken as p < 0.05. The EI was significantly lower in the group with ulcers (0.30±0.07 vs. 0.35±0.07, p = 0.02). Haematological indices were comparable in patients with and without LU. Erythrocyte deformability, but not haematological indices, was associated with LU in patients with SCD.

Priapism in homozygous sickle cell patients: important clinical and laboratory associations

OBJECTIVE

To evaluate the relationship between the occurrence of priapism and important steady-state clinical and laboratory parameters in homozygous sickle cell disease (SCD).

SUBJECTS AND METHODS

Steady-state clinical and laboratory data were obtained from the medical records of 126 male patients seen in the clinic over a 7-year period. Estimated prevalence rates, correlation coefficients and independent t tests were calculated to assess the relationship between priapism and several important clinical and laboratory indices. Patient data on age, haemoglobin concentrations, the frequency of crises per annum, leucocyte counts, platelet counts, serum bilirubin and aspartate transaminase were evaluated.

RESULTS

The prevalence of priapism was determined to be 21.4%, and 22.2% of those affected had erectile dysfunction. There was a significant positive correlation between priapism and older age (p = 0.049) and lower leucocyte counts (p = 0.008). There was no significant relationship with other clinical or laboratory indices.

CONCLUSION

About 1 in 4 of all homozygous older SCD patients had priapism, and an approximately similar ratio developed erectile dysfunction; they also had lower steady-state leucocyte counts. Other clinical and laboratory indicators of disease severity in SCD did not positively correlate with the occurrence of priapism, and this may imply an alternative pathogenetic mechanism.

How I manage priapism due to sickle cell disease

Priapism due to sickle cell disease is a common but less well characterized complication of the disorder. It represents a "medical emergency" with the key determinant of outcome being the duration of penile ischaemia and time to detumescence of <4 h associated with a successful treatment outcome. Management can be outpatient-based and consists of pre-emptive strategies for early stuttering attacks based on prior health education of the association between the 2 disorders, non pharmacological management, outpatient penile aspiration and irrigation with or without instillation of alpha and beta adrenergic agonists for acute episodes and secondary prophylaxis to prevent the high rates of recurrences. The evidence to recommend medical prophylaxis is sparse but based on a consensus of experts and small phase 2 or III clinical trials. A clearer understanding of the molecular mechanism(s) involving normal and dysregulated erectile physiology, scavenger haemolysis and nitric oxide pathway paves way for the use of phosphodiesterase type 5 inhibitors in medical prophylaxis of stuttering attacks. These agents will need to be studied in multi-centre randomized phase III trials before they become standard of care. A multidisciplinary team approach is required to enhance "sexual wellness" and prevent erectile dysfunction in this sexually vulnerable group.

Serum levels of leptin in Nigerian patients with sickle cell anaemia

Background

Several studies have shown that the pathophysiology of homozygous sickle cell anaemia (SCA) results in a myriad of metabolic, nutritional, haematological and clinical effects that interact with other co-morbid factors to determine the quality of life and life expectancy of afflicted patients. Because of its critical roles in nutrition and metabolism, inflammation, haematopoiesis and cellular immunity, this study determined the plasma levels of leptin in steady and unsteady states of HbSS in Nigerian patients.

Methods

A total of 51 SCA patients aged 5 - 35 years with 34 (61.8%) being females who were either on admission or visiting four medical centres in Lagos, Nigeria together with 22 non-SCD controls aged 5 -30 years comprising 12 (54.5%) females were enrolled after obtaining their informed consent and ethical approval. Patients were further stratified into steady and unsteady cases of SCA based on clinical presentations, while blood samples collected by venipuncture from each of the study participants were analyzed haematologically for full blood count and HbF level and microscopically for malaria, while plasma leptin was assayed using ELISA method. Body composition defined by weight, fat mass and body mass index (BMI) was determined using standard methods. Data obtained for cases and controls were analyzed statistically.

Results

Twenty - one patients had unsteady HbSS and elicited greater and significant (P < 0.05) reduction in fat mass, BMI, HbF and eosinophil count but elevated mean total leukocyte, count, level of irreversibly sickled cells and P. falciparum parasitaemia (4613.7 vs. 749.6 - 1078.4 parasites/uL), pyrexia rate (58.3 vs. 25.8%) when compared with steady state patients or non-SCD controls. Compared to the control, significant decreases in plasma leptin before and after controlling for body fat that was worsened by crisis were observed among the SCD patients. Unlike the non-SCD controls, leptin correlated non-significantly (P > 0.05) with all body composition indices measured in the patients except for fat mass in unsteady cases. Multivariate regression analysis identified ESR and RC as independent predictor of low plasma leptin concentration in the SCA patients.

Conclusions

Base on these findings, we conclude that plasma level of leptin is further decreased in the unsteady state of HbSS, shows poor correlation with adiposity and malarial infection but has inflammation and poor reticulocyte response as independent predictors among Nigerian patients.

Hematological indices of sickle cell anaemia patients with pulmonary tuberculosis in northern Nigeria

Nigeria has the fourth highest prevalence of TB and the highest prevalence of Sickle cell anaemia (SCA) in the world. SCA patients have impaired immunity and are vulnerable to TB. Hence, we studied the haematological indices of SCA patients with TB in Nigeria. A total of 23 SCA patients with TB were studied in parallel with equal number of age and sex matched SCA patients without TB. SCA patients with TB had significantly lower haematocrit, higher level of circulating sickle cells (CSCs) and similar level of reticulocyte count in comparison to patients without TB. SCA patients with TB had significantly higher mean WBC count associated with higher frequency of neutrophilia in comparison to those without TB. Monocytosis and eosinopenia were exclusively found in SCA patients with TB at frequencies of 52% and 65% respectively. Lymphocyte and basophil counts were normal in all patients with and without TB. Mean platelet counts were high in both patient groups but the frequency of thrombocytosis was significantly higher in patients with TB. SCA patients with TB had significantly higher mean ESR than their counterparts without the infection. The findings of this study revealed that TB in SCA patients was associated with rising level of CSCs, falling level of haematocrit, sub-optimal reticulocytosis, neutrophilia, monocytosis, thrombocytosis, eosinopenia and rising level of ESR. Hence, SCA patients presenting with these haematological indices should be investigated for TB.