Fetal Rhesus D Genotyping and Sex Determination from Maternal Plasma of Rhesus D-Negative Antenatal Population: The Usefulness of Conventional Polymerase Chain Reaction in Resource-limited Settings

Background. This prospective cohort study evaluated the usefulness of conventional PCR in genotyping fetal Rhesus D (RhD) and sex from the maternal plasma of RhD-negative (RhD−) antenatal population in resource-limited settings. Methods. Thirty apparently healthy RhD− pregnant women with RhD positive (RhD+) partners were included. Blood samples were collected from each participant (in the third trimester of pregnancy) for DNA extraction/purification and fetal RhD genotyping. Results. Out of the 30 samples, 26 (86.7%) were found to be RhD+ while 4 (13.3%) were RhD−. The RhD+ comprised 24 (80.0%) RhD+ based on exons 5, 7, and 10 combined. Exons 5 and 7 were detected in two additional samples but not exon 10. Serological phenotyping of neonatal blood confirmed 26 RhD+ and 4 RhD−. There was a perfect agreement between the fetal RhD genotype and neonatal RhD phenotyping after delivery for exons 5 and 7 (concordance = 100%, κ = 100.0%, diagnostic accuracy = 100%, p < 0.0001 ) while exon 10 presented with an almost perfect agreement (concordance = 93.3%, κ = 76.2%, diagnostic accuracy = 93.3%, p < 0.0001 ). Regarding the prenatal test for the SRY gene, 9 (30.0%) were predicted to be males and the remaining 21 (60.0%) were females. All the 9 and 21 anticipated males and females, respectively, were confirmed after delivery (concordance = 100%, κ = 100.0%, diagnostic accuracy = 100%). Conclusion. Our study suggests that conventional PCR using the SRY, RhD exons 5 and 7 could be useful for predicting fetal sex and RhD from maternal peripheral blood in resource-limited settings.

Download Full-text

Prospective Comparison of Diagnostic Accuracy Between Point-of-Care and Conventional Ultrasound in a General Diagnostic Department: Implications for Resource-Limited Settings

Journal of Ultrasound in Medicine ◽

10.7863/ultra.16.06084 ◽

2017 ◽

Vol 36 (7) ◽

pp. 1453-1460 ◽

Cited By ~ 1

Author(s):

Steffen J.A. Haider ◽

Roberta diFlorio-Alexander ◽

David H. Lam ◽

Joo Y. Cho ◽

Jae Ho Sohn ◽

...

Keyword(s):

Diagnostic Accuracy ◽

Point Of Care ◽

Resource Limited Settings ◽

Resource Limited ◽

Prospective Comparison ◽

Conventional Ultrasound

Download Full-text

Comparison between merthiolate–iodine–formalin and Kato–Katz methods for the diagnosis of human helminth infections in resource-limited settings

Journal of Helminthology ◽

10.1017/s0022149x16000766 ◽

2016 ◽

Vol 91 (6) ◽

pp. 657-664 ◽

Cited By ~ 2

Author(s):

R.N. Incani ◽

T. Homan ◽

E. Pinelli ◽

L. Mughini-Gras ◽

H. Guevara ◽

...

Keyword(s):

Intestinal Parasites ◽

Strongyloides Stercoralis ◽

Field Work ◽

Rural Setting ◽

Fixation Method ◽

Kappa Index ◽

Resource Limited Settings ◽

Perfect Agreement ◽

Resource Limited ◽

Faecal Samples

AbstractDiagnosis of intestinal parasites through examination of fresh faecal samples is hampered by its unpleasantness and the urgent need to detect all parasitic forms. In this paper, we compared the standard Kato–Katz (KK) technique with a traditional fixation method, the merthiolate–iodine–formalin (MIF) method. Two hundred and twenty-seven faecal samples from individuals living in a rural setting in Venezuela with high to moderate prevalences ofAscaris lumbricoides(Al),Trichuris trichiura(Tt) and hookworm infections were examined. The ‘gold standard’ used here was derived from the combination of the outcomes from both methods. KK performed better at detectingTt, and showed higher sensitivity and negative predictive value for bothTtandAl, probably due to a higher capacity of KK to detect low parasite loads. Both methods showed an almost perfect agreement using the Kappa index. MIF provided a higher median of parasitic loads for low and total egg counts for the three helminths. Differentiating fertile from infertile eggs ofAldid not affect the results; infertile eggs were present only at low and intermediate parasitic loads, but absent at high loads. KK was not able to detect high loads of any of the helminths. MIF allowed for the detection of other helminths, such asStrongyloides stercoralis, and protozoan infections, for which KK is not specific. In conclusion, MIF is a simple and inexpensive technique that performs competitively with KK in both laboratory and field work on intestinal helminths, particularly in resource-limited settings.

Download Full-text

The use of 0.01M phosphate buffered saline as detection buffer for Alere Determine® HIV rapid test in resource limited settings

Tanzania Journal of Health Research ◽

10.4314/thrb.v19i2.10 ◽

2017 ◽

Vol 19 (2) ◽

Author(s):

Mariam M. Mirambo ◽

Martha F. Mushi ◽

Ley Shilewangwa ◽

Caroline A. Minja ◽

Benson R. Kidenya ◽

...

Keyword(s):

Negative Impact ◽

Rapid Test ◽

Hiv Positive ◽

Resource Limited Settings ◽

Perfect Agreement ◽

Resource Limited ◽

Rapid Tests ◽

Alternative Detection ◽

Phosphate Buffered Saline ◽

Hiv Negative

Insufficient supply of manufacture’s buffers/diluents in relation to the number of strips per kit has been found to have negative impact on patients’ results. Some laboratories personnel tend to use diluents from other rapid tests manufacturers such as Bioline, Unigold as well as malaria rapid diagnostic test (MRDT). This study aimed at evaluating the use of 0.01M phosphate buffered saline (PBS) as detection buffer for Alere Determine® HIV rapid test. This study was carried out at Bugando School of Medicine in Mwanza, Tanzania. A total of 300 whole blood specimens; 150 HIV positive specimens from patients attending Care and Treatment Centreand 150 HIV negative specimens were retested for HIV status using Alere Determine® HIV rapid test employing normal Alere buffer and 0.01M PBS as buffer.Of the total specimens tested; 150 (100%) of HIV positive were positive by using both Alere buffer and 0.01M PBS while 150(100%) of HIV negative samples were negative by both Alere Determine® and 0.01M PBS. The agreement between 0.01M PBS and Alere Determine® buffer was 100%. The value of kappa indicates perfect agreement between 0.01M PBS and Alere Determine® buffer (100%). A 0.01M PBS is recommended as alternative detection buffer for Alere Determine® in cases of insufficient supply. Further investigation to evaluate the suitable buffer for other rapid tests for HIV and other diseases is recommended especially in resource limited settings.

Download Full-text