Stephen Rulisa

Prof. Stephen Rulisa

Obstetrics and gynecology, University of Rwanda, College of Medicine and Health Sciences, Kigali, Rwanda
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Research Focus & Metrics

Academic Career Length

20Years (2007-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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20 March 2017 in Malaria Journal
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CKChristina T. Kozycki
Christina T. Kozycki
NUNoella Umulisa
Noella Umulisa
SRStephen Rulisa
Stephen Rulisa
EMEmil I. Mwikarago
Emil I. Mwikarago
JMJean Pierre Musabyimana
Jean Pierre Musabyimana
DKDonald J. Krogstad
Donald J. Krogstad
Rapid diagnostic tests (RDTs) for histidine rich protein 2 (HRP2) are often used to determine whether persons with fever should be treated with anti-malarials. However, Plasmodium falciparum parasites with a deletion of the hrp2 gene yield false-negative RDTs and there are concerns the sensitivity of HRP2-based RDTs may fall when the intensity of transmission decreases. This observational study enrolled 9226 patients at three health centres in Rwanda from April 2014 to April 2015. It then compared the sensitivity of RDTs based on HRP2 and the Plasmodium lactate dehydrogenase (pLDH) to microscopy (thick smears) for the diagnosis of malaria. PCR was used to determine whether deletions of the histidine-rich central repeat region of the hrp2 gene (exon 2) were associated with false-negative HRP2-based RDTs. In comparison to microscopy, the sensitivity and specificity of HRP2- and pLDH-based RDTs were 89.5 and 86.2% and 80.2 and 94.3%, respectively. When the results for both RDTs were combined, sensitivity rose to 91.8% and specificity was 85.7%. Additionally, when smear positivity fell from 46 to 3%, the sensitivity of the HRP2-based RDT fell from 88 to 67%. Of 370 samples with false-negative HRP2 RDT results for which PCR was performed, 140 (38%) were identified as P. falciparum by PCR. Of the isolates identified as P. falciparum by PCR, 32 (23%) were negative for the hrp2 gene based on PCR. Of the 32 P. falciparum isolates negative for hrp2 by PCR, 17 (53%) were positive based on the pLDH RDT. This prospective study of RDT performance coincided with a decline in the intensity of malaria transmission in Kibirizi (fall in slide positivity from 46 to 3%). This decline was associated with a decrease in HRP2 RDT sensitivity (from 88 to 67%). While P. falciparum isolates without the hrp2 gene were an important cause of false-negative HRP2-based RDTs, most were identified by the pLDH-based RDT. Although WHO does not recommend the use of combined HRP2/pLDH testing in sub-Saharan Africa, these results suggest that combination HRP2/pLDH-based RDTs could reduce the impact of false-negative HRP2-based RDTs for detection of symptomatic P. falciparum malaria.

21 September 2015 in Scientific Reports
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AMAmy McMillan
Amy McMillan
SRStephen Rulisa
Stephen Rulisa
MSMark W Sumarah
Mark W Sumarah
JMJean M. Macklaim
Jean M. Macklaim
JRJustin Renaud
Justin Renaud
GRGregor Reid
Gregor Reid
Bacterial vaginosis (BV) increases transmission of HIV, enhances the risk of preterm labour and is associated with malodour. Clinical diagnosis often relies on microscopy, which may not reflect the microbiota composition accurately. We use an untargeted metabolomics approach, whereby we normalize the weight of samples prior to analysis, to obtained precise measurements of metabolites in vaginal fluid. We identify biomarkers for BV with high sensitivity and specificity (AUC = 0.99) in a cohort of 131 pregnant and non-pregnant Rwandan women and demonstrate that the vaginal metabolome is strongly associated with bacterial diversity. Metabolites associated with high diversity and clinical BV include 2-hydroxyisovalerate and γ-hydroxybutyrate (GHB), but not succinate, which is produced by bothLactobacillus crispatusand BV-associated anaerobesin vitro. Biomarkers associated with high diversity and clinical BV are independent of pregnancy status and were validated in a blinded replication cohort from Tanzania (n = 45), where we predicted clinical BV with 91% accuracy. Correlations between the metabolome and microbiota identifiedGardnerella vaginalisas a putative producer of GHB and we demonstrate production by this speciesin vitro. This work illustrates how changes in community structure alter the chemical composition of the vagina and identifies highly specific biomarkers for a common condition.

2 May 2017 in PLOS Medicine
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SDStephanie Dellicour
Stephanie Dellicour
ESEsperança Sevene
Esperança Sevene
RMRose McGready
Rose McGready
HTHalidou Tinto
Halidou Tinto
DMDominic Mosha
Dominic Mosha
ASAndy Stergachis
Andy Stergachis
Animal embryotoxicity data, and the scarcity of safety data in human pregnancies, have prevented artemisinin derivatives from being recommended for malaria treatment in the first trimester except in lifesaving circumstances. We conducted a meta-analysis of prospective observational studies comparing the risk of miscarriage, stillbirth, and major congenital anomaly (primary outcomes) among first-trimester pregnancies treated with artemisinin derivatives versus quinine or no antimalarial treatment. Electronic databases including Medline, Embase, and Malaria in Pregnancy Library were searched, and investigators contacted. Five studies involving 30,618 pregnancies were included; four from sub-Saharan Africa (n = 6,666 pregnancies, six sites) and one from Thailand (n = 23,952). Antimalarial exposures were ascertained by self-report or active detection and confirmed by prescriptions, clinic cards, and outpatient registers. Cox proportional hazards models, accounting for time under observation and gestational age at enrollment, were used to calculate hazard ratios. Individual participant data (IPD) meta-analysis was used to combine the African studies, and the results were then combined with those from Thailand using aggregated data meta-analysis with a random effects model. There was no difference in the risk of miscarriage associated with the use of artemisinins anytime during the first trimester (n = 37/671) compared with quinine (n = 96/945; adjusted hazard ratio [aHR] = 0.73 [95% CI 0.44, 1.21], I2 = 0%, p = 0.228), in the risk of stillbirth (artemisinins, n = 10/654; quinine, n = 11/615; aHR = 0.29 [95% CI 0.08–1.02], p = 0.053), or in the risk of miscarriage and stillbirth combined (pregnancy loss) (aHR = 0.58 [95% CI 0.36–1.02], p = 0.099). The corresponding risks of miscarriage, stillbirth, and pregnancy loss in a sensitivity analysis restricted to artemisinin exposures during the embryo sensitive period (6–12 wk gestation) were as follows: aHR = 1.04 (95% CI 0.54–2.01), I2 = 0%, p = 0.910; aHR = 0.73 (95% CI 0.26–2.06), p = 0.551; and aHR = 0.98 (95% CI 0.52–2.04), p = 0.603. The prevalence of major congenital anomalies was similar for first-trimester artemisinin (1.5% [95% CI 0.6%–3.5%]) and quinine exposures (1.2% [95% CI 0.6%–2.4%]). Key limitations of the study include the inability to control for confounding by indication in the African studies, the paucity of data on potential confounders, the limited statistical power to detect differences in congenital anomalies, and the lack of assessment of cardiovascular defects in newborns. Compared to quinine, artemisinin treatment in the first trimester was not associated with an increased risk of miscarriage or stillbirth. While the data are limited, they indicate no difference in the prevalence of major congenital anomalies between treatment groups. The benefits of 3-d artemisinin combination therapy regimens to treat malaria in early pregnancy are likely to outweigh the adverse outcomes of partially treated malaria, which can occur with oral quinine because of the known poor adherence to 7-d regimens. PROSPERO CRD42015032371

23 July 2013 in PLOS ONE
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SRStephen Rulisa
Stephen Rulisa
FKFredrick Kateera
Fredrick Kateera
JBJean Pierre Bizimana
Jean Pierre Bizimana
SASteven Agaba
Steven Agaba
JDJavier Dukuzumuremyi
Javier Dukuzumuremyi
PVPeter J. de Vries
Peter J. de Vries
Rwanda reported significant reductions in malaria burden following scale up of control intervention from 2005 to 2010. This study sought to; measure malaria prevalence, describe spatial malaria clustering and investigate for malaria risk factors among health-centre-presumed malaria cases and their household members in Eastern Rwanda. A two-stage health centre and household-based survey was conducted in Ruhuha sector, Eastern Rwanda from April to October 2011. At the health centre, data, including malaria diagnosis and individual level malaria risk factors, was collected. At households of these Index cases, a follow-up survey, including malaria screening for all household members and collecting household level malaria risk factor data, was conducted. Malaria prevalence among health centre attendees was 22.8%. At the household level, 90 households (out of 520) had at least one malaria-infected member and the overall malaria prevalence for the 2634 household members screened was 5.1%. Among health centre attendees, the age group 5–15 years was significantly associated with an increased malaria risk and a reported ownership of ≥4 bednets was significantly associated with a reduced malaria risk. At the household level, age groups 5–15 and >15 years and being associated with a malaria positive index case were associated with an increased malaria risk, while an observed ownership of ≥4 bednets was associated with a malaria risk-protective effect. Significant spatial malaria clustering among household cases with clusters located close to water- based agro-ecosystems was observed. Malaria prevalence was significantly higher among health centre attendees and their household members in an area with significant household spatial malaria clustering. Circle surveillance involving passive case finding at health centres and proactive case detection in households can be a powerful tool for identifying household level malaria burden, risk factors and clustering.

3 September 2015 in BMC Pregnancy and Childbirth
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Journal Article
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SRStephen Rulisa
Stephen Rulisa
IUImmaculee Umuziranenge
Immaculee Umuziranenge
MSMaria Small
Maria Small
JRJos Van Roosmalen
Jos Van Roosmalen
To determine the prevalence and factors associated with severe (‘near miss’) maternal morbidity and mortality in the University Teaching Hospital of Kigali – Rwanda. We performed a cross sectional study of all women admitted to the tertiary care University Hospital in Kigali with severe “near miss” maternal morbidity and mortality during a one year period using the WHO criteria for ‘near miss’ maternal mortality. We assessed maternal demographic characteristics and disease processes associated with severe obstetric morbidity and mortality. The prevalence of severe maternal outcomes was 11 per 1000 live births. The maternal near miss ratio was 8 per 1000 live births. The majority of severe obstetric morbidity and mortalities resulted from: sepsis/peritonitis (30.2 %)--primarily following caesarean deliveries, hypertensive disease (28.6 %), and hemorrhage (19.3 %). Majority of our patients were found to be of lower socioeconomic status, refered from district hospitals to the tertiary care center, and resided in the eastern part of the country. The main causes associated with MNH were peritonitis, hypertensive disorders and bleeding. The high prevalence of peritonitis may reflect suboptimal intraoperative and intrapartum management of high-risk patients at district hospitals. Direct causes of severe maternal outcome are still the most prevalent. The study identified opportunities for improvement in clinical care to reduce potentially these adverse outcomes.

4 March 2017 in Journal of Ultrasound in Medicine
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PHPatricia C. Henwood
Patricia C. Henwood
DMDavid C. Mackenzie
David C. Mackenzie
ALAndrew S. Liteplo
Andrew S. Liteplo
JRJoshua S. Rempell
Joshua S. Rempell
AMAlice F. Murray
Alice F. Murray
VNVicki E. Noble
Vicki E. Noble