10 research outputs found
Ultrasonographic Splenic Indices Among Paediatric and Adults with Sickle Cell Disease in Nigeria
Background Ultrasonography is an established and reliable method for assessing the spleen. Because of variation due to genetic and other environmental factors including malaria endemicity, interpretation of splenic sizes requires a knowledge of the normal reference range for a given population. The aim of this study was to determine spleen size in different age groups among healthy people in North-Eastern Nigeria and use this as a reference to determine spleen size amongst sickle cell disease (SCD) patients. Methods Using a cross-sectional study design, spleen size was measured in healthy people of different age groups, and steady-state SCD patients (children and adults) using abdominal ultrasonography. Using the age-group specific reference values obtained from the controls, spleens were classified into small, normal size, or enlarged among the SCD patients. Results Abdominal ultrasonography was performed for 313 participants, comprising 109 (34.8%) healthy controls and 204 (65.2%) steady-state SCD patients. The spleen was visualized in all the controls. However, 97(47.6%) of the SCD patients had no visible spleen. Small, normal, and enlarged spleens were observed in 16.7% (n=18/107), 63.6% (n=68/107) and 19.6% (n=21/107) SCD patients, respectively. Compared to the control group, splenic length was three-fold higher in the first two years of life in SCD patients, followed by a progressive age-related decline in size. Enlarged spleens were detected among 5(2.4%) SCD patients by manual palpation method compared to 21 (19.6%) using ultrasonography. Conclusion Model-based age-specific reference ranges and percentile curves for splenic dimensions based on ultrasonography among normal controls in North-Eastern Nigeria were established and may be of value in assessing spleen sizes among SCD patients living in malaria-endemic regions of Africa. Regular spleen scans to assess changes in size can help identify SCD patients at risk of splenomegaly complications including subclinical acute sequestration and hypersplenism, and those who are developing splenic atrophy
Evaluation of two red cell inclusion staining methods for assessing spleen function among sickle cell disease patients in North-East Nigeria
Introduction The loss of splenic function is associated with an increased risk of infection in sickle cell disease (SCD); however, spleen function is rarely documented among SCD patients in Africa, due partly to the non-availability of sophisticated techniques such as scintigraphy. Methods of assessing splenic function which may be achievable in resource-poor settings include counting red blood cells (RBC) containing Howell Jolly Bodies (HJB) and RBC containing silver-staining (argyrophilic) inclusions (AI) using a light microscope. We evaluated the presence of HJB - and AI - containing RBC as markers of splenic dysfunction among SCD patients in Nigeria. Methods We prospectively enrolled children and adults with SCD in steady state attending outpatient clinics at a tertiary hospital in North-East Nigeria. The percentages of HJB- and AI-containing red cells were estimated from peripheral blood smears and compared to normal controls. Results There were 182 SCD patients and 102 healthy controls. Both AI- and HJB-containing red cells could be easily identified in the participants blood smears. SCD patients had a significantly higher proportion of red cells containing HJB (1.5%; IQR 0.7% - 3.1%) compared to controls (0.3%; IQR 0.1% - 0.5%) ( P = 0.0001). The AI red cell counts were also higher among the SCD patients (47.4%; IQR 34.5% - 66.0%) than the control group (7.1%; IQR 5.1% - 8.7%) ( P = 0.0001). The intra-observer reliability for assessment of HJB-(R = 0.92; R 2 = 0.86) and AI-containing red cells (R = 0.90; R 2 = 0.82) was high. The estimated intra-observer agreement was better with the HJB count method (95% limits of agreement, −4.5 to 4.3; P = 0.579). Conclusion We have demonstrated the utility of light microscopy in the assessment of red cells containing - HJB and AI inclusions as indices of splenic dysfunction in Nigerian SCD patients. These methods can be easily applied in the routine evaluation and care of patients with SCD to identify those at high risk of infection and initiate appropriate preventive measures
Clinical and Laboratory Factors Associated with Splenic Dysfunction Among Sickle Cell Disease Patients in a malaria endemic region
Background
Although loss of splenic function is the expected natural course for individuals with sickle cell disease (SCD), factors such as high HbF and coexistence of alpha thalassemia may ameliorate this process. We evaluated factors associated with two surrogate markers of spleen dysfunction - Howell-Jolly bodies (HJB) and argyrophilic inclusion (AI) red cell counts among SCD patients.
Methods
Cross-sectional data of 182 SCD patients (median age 11 years;1- 45 years) and 102 normal controls (median age 12 years;1-32 years) were evaluated. Blood tests including full blood count, serum chemistry and HPLC were performed. The HJB and AI red cell counts were performed on peripheral blood smears.
Results
The percentages of HJB- and AI- red cells rose significantly with increasing age in the SCD group. On regression analysis, frequency of HJB red cells associated positively with MCH (β = 0.289; P = 0.001) and negatively with HbF (β = -0.259; P = 0.002). The AI red cell counts also associated positively with MCH (β = 0.321; P=0.001) and negatively with HbF (β = -0.242; P = 0.020).
Conclusion
Data from this study indicates that the negative association of HbF with both markers of splenic dysfunction among our SCD patients residing in a malaria-endemic region is similar to findings elsewhere of its ameliorating effect on splenic dysfunction
Evaluation of red cell inclusions for assessing spleen function among sickle cell disease patients
Evaluation of two red cell inclusion staining methods for assessing spleen function among sickle cell disease patients in North-East Nigeria
Introduction:
The loss of splenic function is associated with an increased risk of infection in sickle cell disease (SCD); however, spleen function is rarely documented among SCD patients in Africa, due partly to the non-availability of sophisticated techniques such as scintigraphy. Methods of assessing splenic function which may be achievable in resource-poor settings include counting red blood cells (RBC) containing Howell Jolly Bodies (HJB) and RBC containing silver-staining (argyrophilic) inclusions (AI) using a light microscope. We evaluated the presence of HJB - and AI - containing RBC as markers of splenic dysfunction among SCD patients in Nigeria.
Methods:
We prospectively enrolled children and adults with SCD in steady state attending outpatient clinics at a tertiary hospital in North-East Nigeria. The percentages of HJB - and AI-containing red cells were estimated from peripheral blood smears and compared to normal controls.
Results:
There were 182 SCD patients and 102 healthy controls. Both AI- and HJB-containing red cells could be easily identified in the participants blood smears. SCD patients had a significantly higher proportion of red cells containing HJB (1.5%; IQR 0.7% - 3.1%) compared to controls (0.3%; IQR 0.1% - 0.5%) (P <0.0001). The AI red cell counts were also higher among the SCD patients (47.4%; IQR 34.5% - 66.0%) than the control group (7.1%; IQR 5.1% - 8.7%) (P < 0.0001). The intra-observer reliability for assessment of HJB- (r = 0.92; r2 = 0.86) and AI- containing red cells (r = 0.90; r2 = 0.82) was high. The estimated intra-observer agreement was better with the HJB count method (95% limits of agreement, -4.5% to 4.3%; P = 0.579).
Conclusion:
We have demonstrated the utility of light microscopy in the assessment of red cells containing - HJB and AI inclusions as indices of splenic dysfunction in Nigerian SCD patients. These methods can be easily applied in the routine evaluation and care of patients with SCD to identify those at high risk of infection and initiate appropriate preventive measures
Ultrasonographic assessment of spleen size and pattern of change among sickle cell disease patients and healthy controls in North-Eastern Nigeria
Background: Ultrasonography is an established and reliable method for assessing the spleen. Because of variation due to genetic and other environmental factors including malaria endemicity, interpretation of spleen sizes requires a knowledge of the normal reference range for a given population. This study aimed to identify spleen size reference ranges across age groups of healthy controls to serve as a baseline to assess changes in spleen size in patients with sickle cell disease.
Methods: Using a cross-sectional study design, spleen size was measured in healthy people of different age groups and steady-state sickle cell disease patients (children and adults) using abdominal ultrasonography. Using the age-group-specific reference values obtained from the controls, spleens were classified into small, normal size or enlarged among the sickle cell disease patients.
Results: The study consisted of 109 (34.8%) healthy controls and 204 (65.2%) steady-state sickle cell disease patients. The spleen was visualised in all the controls ( n = 109) and in 107 (52.4%) sickle cell disease patients. Using cut-off values for spleen length among the controls across age groups (< 5 years (5.0–7.0 cm); 5–9 years (5.5–8.5 cm); 10–14 years (6.0–11.0 cm) and ⩾ 15 years (7.0–12.5 cm)), spleen size was classified as small ( n = 18/204; 8.87%), normal ( n = 68/204; 33.3%) and enlarged ( n = 21/204; 10.3%) among the sickle cell disease patients.
Conclusion: Model-based age-group reference ranges and percentile curves for splenic dimensions based on ultrasonography among normal controls in North-Eastern Nigeria were established and may be of value in assessing spleen sizes among sickle cell disease patients living in malaria-endemic regions of Africa
Clinical and laboratory factors associated with splenic dysfunction among sickle cell disease patients
Evaluation and validation of room temperature biospecimens transportation and storage technologies as an alternative cost effective solution to cold chain logistics and storage within biobanking and/or diagnostics
Thesis (MSc)--Stellenbosch University, 2017ENGLISH ABSTRACT :
Background: Cold chain management (CCM) is an important aspect of biobanking
operation. However challenges such as constant power failure, limited access to dry ice transport and storage of human samples collected at various sites all over the world or at
difficult out of reach places.
and liquid nitrogen, transport logistics and courier delays especially in Africa becomes a
major challenge. Ensuring samples are maintained at the proper temperature throughout
all processes is imperative to maximal long term viability and usability. Thus we consider
room temperature storage (RTS) technologies as an innovative, cost effective and green
alternative to cold chain logistics.
Methods: Various room temperature storage technologies were evaluated for the
stabilization and storage of whole blood DNA and RNA, buffy coat, genomic DNA and
urine DNA. The stabilizers include the Biomatrica liquid gard technology and dry matrix
technology as well as DNAgenotek Hemagene buffy-coat stabilizers, Paxgene RNA and
Norgen urine tubes. Samples were stored with and without a stabilizer under different
temperature conditions namely room temperature, 45oC,-80oC, -20oC and liquid nitrogen (-
196oC) over different time periods to determine effect on sample integrity and quality. At
the end of each time point DNA/RNA was extracted and the integrity of the samples
determined by assessing the concentration, purity and integrity. Further downstream
analysis such as polymerase chain reaction (PCR), quantitative real time PCR and DNA
sequencing was conducted. In addition, a shipping cost analysis between satellite sites in
African and our biobank was done to compare frozen and room temperature shipping.
Results The study results show that sample integrity/quality for biospecimens stored at
room temperature with stabilizers were comparable and more cost effective than cold
chain storage systems. In addition some stabilizers showed better stabilizing properties
than others.
Conclusion: Room temperature storage provides an innovative and cost effective method
of storage and shipping to cold chain management systems (CCM). Green technologies
forms a small part of biobanking operations however its results would be beneficial as low
energy options for biobanking are particular critical in low resource settings which have
infrastructural challenges. In turn, it would also be a more cost-effective option for the transport and storage of human samples collected at various sites all over the world or at
difficult out of reach places.AFRIKAANSE OPSOMMING : Agtergrond: Koue ketting bestuur (KKB) is 'n belangrike aspek van Biobank
bedrywighede, maar uitdagings soos konstante kragonderbrekings, beperkte toegang tot
droë ys en vloeibare stikstof, vervoer logistiek en koerier vertragings veral in Afrika is 'n
groot uitdaging. Om te verseker dat monsters in stand gehou word by die regte
temperatuur, in die hele proses, is dit noodsaaklik om lang lewensvatbaarheid en
bruikbaarheid van monsters te maksimiseer. Dus kyk ons na kamertemperatuur stoor
tegnologie as 'n innoverende, koste-effektiewe en groen alternatief vir koue ketting
logistiek.
Metodes: Verskeie kamertemperatuur stoor tegnologie is geëvalueer vir die stabilisering
en stoor van heelbloed DNA en RNA, “buffy coat”, genomiese DNA en uriene DNA. Die
stabiliseerders sluit in die Biomatrica vloeibare beskerm-tegnologie en droë matriks
tegnologie asook DNAgenotek, Hemagene “buffy coat” stabiliseerders, Paxgene RNA en
Norgen urienbuise. Monsters is gestoor met en sonder 'n stabiliseerder by verskillende
temperature naamlik kamertemperatuur, 45oC, -80oC, -20oC en in vloeibare stikstof (-
196oC) oor verskillende tydperke om die uitwerking op monster integriteit en kwaliteit te
bepaal. Aan die einde van elke tydperk is DNA / RNA geisoleer en die integriteit, kwaliteit
en konsentrasie van elke monsters is bepaal en geëvalueer. Verdere stroomaf ontleding
soos Polimerase Kettingreaksie (PKR), kwantitatiewe “real-time” PKR en DNA
volgordebepaling is gedoen. Hierby is 'n koste-ontleding tussen satelliet gebiede in Afrika
en ons Biobank gedoen om bevrore en kamertemperatuur monsters wat aangestuur is na
die lande te vergelyk.
Resultate: Die studie wys dat die integriteit/kwaliteit van monsters wat by kamer
temperatuur gestoor was in stabiliseerders, vergelykbaar en meer koste-doeltreffend as
koueketting stoor stelsels was. Daarbenewens het 'n paar stabiliseerders beter
stabiliserende eienskappe as ander getoon. Gevolgtrekking: Kamertemperatuur berging bied 'n innoverende en meer kosteeffektiewe
metode vir die stoor en stuur van monsters as koue ketting bestuurstelsels.
Groen tegnologie vorm 'n kleindeel van Biobank bedrywighede, maar die resultate sal
egter voordelig wees as lae energie-opsies vir Biobank bedrywighede, en is besonder
krities in lae hulpbron instellings wat uitdagings met infrastruktuur ervaar. Op sy beurt, sou
dit ook 'n meer koste-effektiewe opsie wees vir die vervoer en berging van menslike
monsters na verskillende plekke oor die wêreld of in moeilike bereikbare plekke
Knowledge, risk perception and uptake of COVID-19 vaccination among internally displaced persons in complex humanitarian emergency setting, Northeast Nigeria
Abstract Background Owing to crowded and unsanitary conditions, internally displaced persons (IDPs) have an increased risk of COVID-19 infection. Adoption of COVID-19 preventive measures among this population is premised on accurate information, adequate knowledge, and risk perception. We assessed COVID-19 knowledge and risk perception and investigated the association between risk perception and COVID-19 preventive measures, including vaccination among IDPs in Northeast Nigeria. Methods We conducted a cross-sectional study during July–December 2022 and sampled 2,175 IDPs using stratified sampling. We utilized a 12-point assessment tool to evaluate COVID-19 knowledge. Participants who scored ≥ 6 points were considered to have adequate knowledge. We used a 30-item Risk Behavior Diagnosis Scale to assess COVID-19 risk perception and evaluated each item on a 5-point Likert scale. Participants were divided into risk perception categories by the median of Likert scale scores. We performed weighted logistic regression analysis to identify factors associated with risk perception. Pearson’s chi-squared with Rao-Scott adjustment was used to determine the relationship between risk perception and COVID-19 preventive measures. Results Of 2,175 participants, 55.7% were 18–39 years old, 70.9% were females, and 81.7% had no formal education. Among the IDPs, 32.0% (95% CI: 28.8 – 35.0) were considered to have adequate COVID-19 knowledge, and 51.3% (95% CI: 47.8 – 54.8) perceived COVID-19 risk as high. Moreover, 46.3% (95% CI: 42.8 – 50.0) had received one dose of COVID-19 vaccine, and 33.1% (95% CI: 29.8 – 36.0) received two doses. Adequate knowledge (Adjusted Odds Ratio (AOR) = 2.10, [95% CI: 1.46 – 3.03]) and post-primary education (AOR = 3.20, [95% CI: 1.59 – 6.46]) were associated with risk perception. Furthermore, high risk perception was significantly associated with wearing face masks (χ2 = 106.32, p-value < .001), practicing hand hygiene (χ2 = 162.24, p-value < .001), physical distancing (χ2 = 60.84, p-value < .001) and vaccination uptake (χ2 = 46.85, p-value < .001). Conclusions This study revealed gaps in COVID-19 knowledge, risk perception, and vaccination uptake but demonstrated a significant relationship between risk perception and COVID-19 preventive practices. Health education and risk communication should be intensified to improve knowledge, elicit stronger risk perception, and enhance COVID-19 preventive practices