Barriers and Facilitators of Premarital Genetic Counseling for Sickle Cell Disease in Northern Nigeria.

In high-income countries, premarital genetic counseling for Sickle Cell Disease (SCD) is a standard practice. However, in Nigeria, there is no formal premarital genetic counseling program available for SCD. We conducted a series of focus group discussions with health care professionals, patients with SCD, and parents of the patients with or without SCD to gain an understanding of their attitudes and beliefs towards SCD/Sickle Cell Trait and premarital genetic counseling for SCD. Data were analyzed using Charmaz's constructivist grounded theory approach. Two themes were highlighted in the analysis as follows: (1) the difference between the perception of premarital sickle cell screening among individuals with SCD versus the general population, and (2) the personal beliefs and physical challenges that could lead to the avoidance of premarital screening within the general community. Lack of disease-related knowledge, testing facilities, transportation, and stigma associated with the disease were the most commonly perceived barriers to premarital testing. Also, a willingness to receive premarital testing for SCD exists within our community to reduce the spread of the disease and advocate for improved health-related quality of life of patients with SCD. The content and structure of a premarital genetic counseling program in Kano, Northern Nigeria, needs to be developed.

Non-S Sickling Hemoglobin Variants: Historical, Genetic, Diagnostic, and Clinical Perspectives.

Apart from hemoglobin-S (HbS), there are other Hb variants (non-S sickling Hb variants) that cause sickle cell disease. However, the profiles of these non-S sickling Hb variants have neither been collated nor harmonized. A literature search revealed 14 non-S sickling Hb variants (HbC-Harlem, HbC-Ziguinchor, HbS-Travis, HbS-Antilles, HbS-Providence, HbS-Oman, HbS-Cameroon, HbS-South End, Hb Jamaica Plain, HbC-Ndjamena, HbS-Clichy, HbS-San Martin, HbS-Wake, and HbS-São Paulo). Generally, the non-S sickling Hb variants are double mutants with the HbS mutation (GAG>GTG: ßGlu6Val) and additional ß-chain mutations. Consequently, non-S sickling Hb variants give positive solubility and sickling tests, but they differ from HbS with respect to stability, oxygen affinity, and electro-chromatographic characteristics. Similarities and discrepancies between HbS and non-S sickling Hb variants create diagnostic pitfalls that can only be resolved by elaborate electro-chromatographic and/or genetic tests. It is therefore imperative that tropical hematologists should have a thorough understanding of these atypical sickling Hb variants. Collated and harmonized appraisal of the non-S sickling Hb variants have not been previously undertaken. Hence, this paper aims to provide a comprehensive but concise historical, genetic, comparative, diagnostic, and clinical overview of non-S sickling Hb variants. The elaborate techniques often required for precise diagnosis of non-S sickling Hb variants are regrettably not readily available in low resource tropical countries, which paradoxically carry the heaviest burden of sickling disorders. We strongly recommend that tropical countries should upgrade their diagnostic laboratory facilities to avoid misdiagnosis of these atypical Hb mutants.

Pyopericardium with Cardiac Tamponade in a Nigerian Child with Acute Osteomyelitis.

In pyopericardium, pus accumulates in the pericardial space as a result of infection by pyogenic organisms, most common of which are Staphylococcus aureus and Mycobacterium tuberculosis. These patients are at risk of cardiac tamponade. Apart from pericardiocentesis in the management of these patients, definitive drug treatment may pose a formidable challenge in a setting of coinfection as in patients with tuberculosis who are predisposed to secondary bacterial infections. This was the case of our patient. We here highlight the challenges faced with etiologic diagnosis in resource-limited settings.

Hematological parameters in sickle cell anemia patients with and without priapism.

BACKGROUND: Priapism was associated with certain hematological parameters in sickle cell anemia (SCA) patients in one report but not in another. We studied differences in haematological parameters between SCA patients with and without priapism. PATIENTS AND METHODS: Eighteen patients with SCA who presented with acute priapism during the years 2001-2004 were compared with age- and sex-matched SCA patients without priapism with respect to hematocrit, reticulocyte count, level of irreversibly sickled cells (ISC), percentage of haemoglobin F (Hb F), total leukocyte and platelet counts. RESULTS: SCA patients with priapism had a mean hematocrit of 0.28 L/L, which was significantly higher than the mean hematocrit value of 0.24 L/L (P<0.05) in patients without priapism. The mean reticulocyte count of 8% in patients with priapism was significantly lower than mean reticulocyte count of 12% (P<0.05) in patients without priapism. The level of ISC of 3% in patients with priapism was significantly lower than the level of 6.5% (P<0.05) in patients without priapism. There was no statistically significant difference in the mean levels of Hb F (7% vs. 6%). Patients with priapism had a mean leukocyte count and mean platelet count that did not significantly differ from values in patients without priapism. CONCLUSIONS: SCA patients with priapism had a lower rate of hemolysis, resulting in a higher hematocrit and greater blood viscosity, which increased the risk of corpora cavernosal sickling and blockade. Hence, a relatively high hematocrit is a risk factor for the development priapism in patients with sickle cell anemia.

The Pathophysiologic Basis of Anaemia in Patients with Malignant Diseases.

Cancer patients frequently present with anaemia that may result from the direct or indirect effects of the tumor or its treatment. Anaemia is an independent adverse prognostic factor that exerts negative influence on quality of life and survival of cancer patients. Anaemia in malignant disorders often arises from an interplay of multiple aetiological and pathophysiologic mechanisms. Understanding these mechanisms will help the oncologist identify and treat specific causes of the anaemia thereby minimizing the use of blood transfusion, which is associated with many adverse effects. This paper reviewed the various aetiological and pathophysiologic mechanisms of anaemia in cancer patients including direct and indirect tumour effects that lead to reduced red cell production or increased red cell destruction via a myriad of mechanisms ranging from marrow infiltration and cancer-associated acute myelonecrosis to chronic inflammation, blood loss, iron, folate, vitamin B12 and other nutrients deficiencies, malignancy related renal injury, pure red cell aplasia, hypersplenism, haemophagocytic syndrome, red cell autoantibody production, non-immune red cell fragmentation and cytotoxic therapy-induced erythroid cell apoptosis and eryptosis. Hence anaemia in cancer patients is attributable to a wide spectrum of aetiological factors with multiple and sometimes overlapping pathophysiologic mechanisms. It is therefore necessary for the oncologists to thoroughly investigate all cases of anaemia with the aim of identifying the actual causative factors in order to offer more sustainable cause-specific treatment modalities that will minimize the use of blood transfusion with its attendant adverse effects.

Impact of sickle cell trait on the thrombotic risk associated with non-O blood groups in northern Nigeria.

BACKGROUND: The non-O blood group is an established risk factor for deep vein thrombosis (DVT), while controversy surrounds the role of sickle cell trait (SCT) as a risk factor for DVT. We hypothesised that if SCT is a risk factor for DVT, individuals with non-O blood groups and SCT (Hb AS) would have a higher risk of DVT than their counterparts with non-O blood groups and normal haemoglobin phenotype (Hb AA). MATERIALS AND METHODS: We retrospectively analysed the prevalence of SCT and non-O blood groups among 148 DVT patients with control subjects in order to determine the role of SCT as a risk factor for DVT and its impact on the risk of DVT among patients with non-O blood groups. RESULTS: In comparison with control subjects, DVT patients had significantly higher prevalences of SCT (35.1% vs 27.7%, p=0.04) and non-O blood groups (68.9% vs 45.9%, p=0.02). The odds ratios for DVT due to SCT, non-O blood groups with normal Hb phenotype (Hb AA) and non-O blood groups with SCT (Hb AS) were 1.3, 2.4 and 3.5, respectively. DISCUSSION: These results suggest that SCT by itself is a weak risk factor for DVT but it has the potential of escalating the DVT risk among patients with non-O blood groups. The combined effects of elevated clotting factors (non-O group effect) and increased clotting factor activation (SCT effect) were responsible for the escalated DVT risk among patients with co-inheritance of non-O blood groups and SCT. Co-inheritance of SCT and non-O blood group is, therefore, an important mixed risk factor for DVT. This should be taken into account when assessing DVT risk profiles of patients in Africa and other parts of the world where the SCT is prevalent.