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

Strategies to increase access to basic sickle cell disease care in low- and middle-income countries

INTRODUCTION

Sickle cell disease (SCD) is the most common hemoglobinopathy in the world. Over 90% of those born with SCD live in low- and middle-income countries (LMICs), yet individuals in these settings have much poorer outcomes compared to those in high-income countries.

AREAS COVERED

This manuscript provides an in-depth review of the cornerstones of basic SCD care, the barriers to implementing these in LMICs, and strategies to increase access in these regions. Publications in English language, peer-reviewed, and edited from 2000 to 2021 were identified on PubMed. Google search was used for gray literature.

EXPERT OPINION

Outcomes for patients with SCD in high-income countries have improved over the last few decades due to the implementation of universal newborn screening programs and use of routine antimicrobial prophylaxis, increase in therapeutic and curative options, and the adoption of specific measures to decrease risk of stroke. This success has not translated to LMICs due to several reasons including resource constraints. A combination of several strategies is needed to increase access to basic SCD care for patients in these settings.

Clinical and Molecular Approach to Adult-Onset, Neoplastic Monocytosis

PURPOSE OF REVIEW

In this review, we provide a comprehensive and contemporary understanding of malignant monocytosis and provide a framework by which the appropriate diagnosis with malignant monocytosis can be rendered.

RECENT FINDINGS

Increasing data support the use of molecular data to refine the diagnostic approach to persistent monocytosis. The absence of a TET2, SRSF2, or ASXL1 mutation has ≥ 90% negative predictive value for a diagnosis of CMML. These data may also reliably differentiate chronic myelomonocytic leukemia, the malignancy that is most associated with mature monocytosis, from several other diseases that can be associated with typically a lesser degree of monocytosis. These include acute myelomonocytic leukemia, acute myeloid leukemia with monocytic differentiation, myelodysplastic syndromes, and myeloproliferative neoplasms driven by BCR-ABL1, PDGFRA, PDGFRB, or FGFR1 rearrangements or PCM1-JAK2 fusions among other rarer aberrations. The combination of monocyte partitioning with molecular data in patients with persistent monocytosis may increase the predictive power for the ultimate development of CMM but has not been prospectively validated. Many conditions, both benign and malignant, can be associated with an increase in mature circulating monocytes. After reasonably excluding a secondary or reactive monocytosis, there should be a concern for and investigation of malignant monocytosis, which includes hematopathologic review of blood and marrow tissues, flow cytometric analysis, and cytogenetic and molecular studies to arrive at an appropriate diagnosis.

Sickle Cell Disease and Infections in High- and Low-Income Countries

Infections, especially pneumococcal septicemia, meningitis, and Salmonella osteomyelitis, are a major cause of morbidity and mortality in patients with sickle cell disease (SCD). SCD increased susceptibility to infection, while infection leads to SCD-specific pathophysiological changes. The risk of infectious complications is highest in children with a palpable spleen before six months of age. Functional splenectomy, the results of repeated splenic infarctions, appears to be a severe host-defense defect. Infection is the leading cause of death, particularly in less developed countries. Defective host-defense mechanisms enhance the risk of pneumococcal complications. Susceptibility to Salmonella infections can be explained at least in part by a similar mechanism. In high-income countries, the efficacy of the pneumococcal vaccine has been demonstrated in this disease. A decreased in infection incidence has been noted in SCD patients treated prophylactically with daily oral penicillin. Studies in low-income countries suggest the involvement of a different spectrum of etiological agents.

How I investigate monocytosis

Monocytosis is a common finding that is caused by a wide variety of neoplastic and non-neoplastic conditions. The adequate evaluation of monocytosis involves the integration of laboratory data, morphology, clinical findings, and the judicious use of ancillary studies. We review the literature on monocytosis, including the 2017 revised 4th edition of the World Health Organization classification of hematopoietic neoplasms. We present a review of monocytosis with practical guidelines on how to approach both routine and challenging cases.

Defective lipid metabolism in sickle cell anaemia subjects in vaso-occlusive crisis

Background:

Abnormal lipid homeostasis has been reported in sickle cell anaemia (SCA) as well as in other haematological disorders. However, there is little information on the lipid profile of SCA subjects in vaso-occlusive crisis (VOC). This study determined the lipid profile of adult SCA subjects in VOC and in steady state (SSCA).

Materials and Methods:

Fifty-eight (58) adults with HbSS (30 in steady state and 28 in vaso-occlusive crisis) and 24 age-matched healthy individuals with HbAA genotype were recruited into this study. Standard methods were used for the determination of blood pressure (BP), packed cell volume (PCV), total white blood cell count (WBC) and haemoglobin phenotype. After an overnight fast, 5 ml of venous blood was obtained from each SSCA and the controls while samples were collected upon admission in the VOC group. Plasma lipid profile was determined using enzymatic method. Differences between two groups were determined using independent Student's t-test or Man-Whitney U as appropriate. P-values less than 0.05 were considered significant.

Results:

Plasma total cholesterol (TC) and high density lipoprotein (HDL) were significantly lower while the ratio of triglyceride (TG) to HDL (TG/HDL) was significantly higher in SSCA compared with the controls. Low density lipoprotein (LDL) and TC were significantly lower in SCA subjects in VOC compared with controls. However, TC, TG, LDL and TG/HDL were significantly lower while HDL was significantly higher in VOC compared with SSCA.

Conclusion:

Sickle cell anaemia subjects have defective fasting lipid metabolism which becomes pronounced with VOC.

Musculoskeletal complications among children with sickle cell admitted in university of Nigeria teaching hospital ituku - ozalla enugu: a 58 month review

BACKGROUND

Sickle cell anemia (SCA) is a genetic hematological disorder characterized by red blood cells that assume abnormal, rigid, and sickle shape. The musculoskeletal complications of SCA result from vessel occlusion, leading to tissue ischemia and infarction and progressive end organ damage.

AIM

The aim of this study was to determine the pattern of musculoskeletal complications among children with SCA admitted at the University of Nigeria Teaching Hospital (UNTH) Ituku Ozalla.

SUBJECTS AND METHODS

This is a retrospective study of cases of musculoskeletal complications among SCA patients admitted in UNTH over a 58 month period. Data were analyzed using the SPSS version 20 and GraphPad Prism 5 soft-wares. Variables analyzed include musculoskeletal complications, age and gender distribution of subjects. Fisher's exact was used to test for significant association of categorical variables while Mann Whitney U-test was used to compare the means. A P value of less than 0.05 was accepted as significant.

RESULTS

There were 300 registered patients in our sickle cell clinic. A total of 78 patients (52 males and 26 females) were admitted between January 2007 and October 2012. The median age of the patients was 10 years (range: 9 months to 17 years). 25 of the 78 patients had musculoskeletal complications, giving a prevalence rate of 32.1%. The most common musculoskeletal complication was acute osteomyelitis, diagnosed in 10/78 (12.8%) of the patients.

CONCLUSION

Acute osteomyelitis is the most common musculoskeletal complications in children with SCA attending UNTH Ituku Ozalla.

Steady state hemoglobin concentration and packed cell volume in homozygous sickle cell disease patients in Lagos, Nigeria

BACKGROUND

Sickle cell disease is a genetic disorder of hemoglobin causing myriad of pathology including anemia. The purpose of this study was to evaluate the baseline values of steady state hemoglobin and packed cell volume as a guide to managing the early recognition of hemolytic crises in sickle cell anemia.

METHODS

A cross-sectional study was conducted among the sickle cell patients attending the Sickle Cell clinic of Lagos State University Teaching Hospital, Ikeja. A blood sample of 4.5 ml blood was collected from each participant for hemoglobin concentration and packed cell volume. All blood samples were also screened for HIV and hemoglobin phenotypes were done using cellulose acetate hemoglobin electrophoresis at pH 8.6.

RESULTS

A total of 98 subjects in steady state were recruited, consisting of 53 (54.1%) females and 45 (45.9%) males. The overall means were 7.92±1.49 and 24.46±4.76; a female mean of 7.73±1.45; 23.89±4.60, and a male mean of 8.14±1.54 and 25.14±4.91 were obtained for hemoglobin and packed cell volume, respectively. Sixty - nine of the 98 (70.40%) subjects have been previously transfused with blood.

CONCLUSION

The mean hemoglobin concentration and packed cell volume in males was higher than females. The overall mean was lower than what was expected for age and sex. Over two-third of sickle cell anemia population had been transfused.

The role of infection in the pathogenesis of vaso-occlusive crisis in patients with sickle cell disease

Sickle cell disease (SCD) is characterized by recurrent vaso-occlusive crisis (VOC). Patients with SCD have impaired immunity and are thus predispose to infections. The vast majority of SCD patients live in underdeveloped nations with high prevalence and transmission rates of infections. This makes the SCD patients prone to infections, which frequently precipitate VOC. We reviewed the role of infection in the pathogenesis of VOC, taking into consideration all potential mechanisms from previous studies and hypothetical perspectives. The potential mechanisms through which infections may lead to VOC involve several pathological changes including pneumonitis, pyrexia, acute phase reaction, hypercoagulability, neutrophilia, eosinophilia, thrombocytosis, bronchospasm, red cell cytopathic and membrane changes, auto-antibodies mediated red cell agglutination and opsonization, diarrhoea and vomiting, which may act singly or in concert to cause red cell sickling. These changes can induce sickling directly or indirectly through their adverse effects on Hb oxygenation and polymerization, hydration, blood viscosity, red cell metabolism, procoagulant activation, intercellular adherence and aggregation, culminating in VOC. There is therefore the need to ameliorate the burden of infection on SCD through immunization, prophylactic and therapeutic use of antimicrobials, barrier protection and vector control in communities with high prevalence of SCD.

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.