Indirect Determination of Hematological Reference Intervals in Healthy Moroccan Adults Using Outpatient Data.

BACKGROUND: Reference intervals are essential for the interpretation of clinical laboratory tests and patient management. This study aims to determine age and gender reference intervals of complete blood count (CBC) in the Moroccan population by using the indirect approach. METHODS: The study used data of ostensibly healthy adults collected retrospectively using the laboratory information system (LIS) of the Laboratory for Research and Medical Analysis of the Fraternal Royal Gendarmerie in Rabat (Morocco), between January 2018 and February 2020. The study included 5,898 men and 10,172 women ranging in age from 18 to 90 years. The lower and upper reference limits of CBC parameters were calculated using the nonparametric technique, as suggested by the Clinical and Laboratory Standards Institute (CLSI). RESULTS: All hematological parameters showed no clinically significant gender-related differences, except small differences in the values of hemoglobin (HB), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH) and mean corpuscular hemoglobin concentration (MCHC). There were also no clinically significant agerelated differences for median values of all hematology analytes in both genders, except for platelet count (PLT) that continued to decline with increasing age in men and women, and Red blood cell count (RBC), Hematocrit (HCT), and hemoglobin (HB) that tended to increase with age but decrease in older age groups in men while they tended to increase with age in women. CONCLUSIONS: The indirect method can be used to establish reference intervals for CBC, with appropriate selection criteria and statistical tools. Our findings differed from the reference ranges provided in the textbook and also in other countries' reports.

Age-and Gender-Specific Reference Intervals for Systemic Inflammatory Indicators in Healthy Moroccan Adults.

BACKGROUND: Neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), lymphocyte-to-monocyte ratio (LMR) and the systemic immune inflammation index (SII) are effective prognostic markers of patients in various clinical situations such as cancer, cardiovascular diseases and inflammatory diseases. This study aims to explore the reference values based on gender and age for NLR, PLR, LMR and SII in the Moroccan population. METHODS: From January 2018 to February 2020, data of ostensibly healthy adults were collected retrospectively from the laboratory information system (LIS) of the Laboratory for Research and Medical Analysis of the Fraternal Royal Gendarmerie, Rabat (Morocco). A total of 5,898 men and 10,172 women aged between 18 and 90 years were included. RIs of each parameter were established and validated in accordance with the Clinical and Laboratory Standards Institute (CLSI) document C28-A3. RESULTS: NLR was significantly different between men and women (p < 0.05), while PLR, LMR and SII were not. The values of NLR, PLR, LMR and SII differed significantly between different age groups of both genders (p < 0.05). Therefore, RI of PLR, LMR, and SII had to be divided into groups based on age, but not on gender, while establishing the NLR reference intervals took into account both factors; age and gender. CONCLUSIONS: This paper provides Reference Intervals for NLR, PLR, LMR, and SII according to age and gender in healthy Moroccan adults. This can improve assessment and potentially widen the use of these biomarkers in Moroccan clinical context.

Neutralising antibodies against SARS-CoV-2 give important information on Covid-19 epidemic evolution in Rabat, Morocco, March 2020-February 2021.

Background: The SARS-CoV-2 is an extremely contagious and acute viral disease mainly affecting humans. Objective: To estimate seroprevalence of SARS-CoV-2 neutralizing antibodies (NAbs) for illegible armed force individuals living in Rabat, Morocco. Method: A convenience sample (N = 2662) was conducted from May 2020 to February 2021. We used the standard neutralization assay to quantify the NAbs titers. A serum was positive when the titer was 1:4. High positive NAbs titers were defined when ≥ 1:32. Results: Demographic and socioeconomic status did not affect seroprevalence data. An overall seroprevalence of 24,9% was found. Sera from blood donors, young recruits and auto-immune population had lower NAbs titers. However, titers were above 1:16 in 9% of the population with high risk of SARS-CoV-2 exposure. Seropositivity increased over time with values reaching peaks after the epidemic waves (2.4% in May 2020; 16.2% in August 2020; 22.7% in December 2020 and 37% in February 2021). Conclusion: And increase of NAbs was observed over time and correlated with the post-epidemic waves of COVID-19 in Morocco.