ABSTRACT
Containment of pandemic infections mainly depends on prompt identification of carriers, achievable through strict surveillance and truthful diagnostic testing. Although molecular identification of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the gold standard method, its low sensitivity and long turnaround time are among major concerns. In this retrospective single-center study, we reviewed the results of the lymphocyte and neutrophil counts of 1450 Iranian patients with coronavirus disease 2019 (COVID-19) recruited at Baqiyatallah Hospital, Tehran, Iran. Of 1450 patients, 439 cases (30.3%) were polymerase chain reaction (PCR) negative;further emphasizing that getting negative molecular testing is not as reliable as a positive result. While the lymphocyte count in cases with less than 50 years old was 1.8x103/ micro L (1.2-2.5), it was 1.47x103/ micro L (0.84-2.16) in the older group (p < 0.001). Also, men experienced lower lymphocytes as compared to women (1.53x103/ micro L vs 1.76x103/ micro L;p=0.002). Of particular interest, the lymphocyte count in the PCR-negative cases was 1.77x103/ micro L (0.98-2.45) which was significantly higher than its count in their positive counterparts (1.53x103/ micro L;p=0.004). Unlike lymphocytes, sex and PCR did not significantly affect the number of neutrophils. The odds ratio for neutrophilia in patients aged older than 50, either with a negative or a positive PCR, was 2.46 and 2.23, suggesting old age as the most significant associated factor. The number of lymphocytes along with increased neutrophil count may probably serve as simple, rapid, and economical biomarkers, and are seemingly appropriate items that should be taken into account in the identification of patients with COVID-19, especially those aged more than 50.
ABSTRACT
Background and Objectives: Several studies have focused on the alterations of hematological parameters for a better un-derstanding of the COVID-19 pathogenesis and also their potential for predicting disease prognosis and severity. Although some evidence has indicated the prognostic values of thrombocytopenia, neutrophilia, and lymphopenia, there are conflicting results concerning the leukocyte and monocyte count. Materials and Methods: In this retrospective Double Centre study, we reviewed the results of WBC and monocyte counts of 1320 COVID-19 patients (243 of whom (18.4%) had severe disease) both on admission and within a 7-day follow-up. Results: We found that both the number of monocytes and the percentage of monocytosis were higher in the severe group;however, it was not statistically significant. On the other hand, we found that not only the mean number of WBCs was significantly higher in the severe cases also leukocytosis was a common finding in this group;indicating that an increased number of WBC may probably predict a poor prognosis. Also, the monocyte count was not affected by age;however, univariate analysis showed that the percentage of leukocytosis was significantly greater in the older group (>50) with an odds ratio of 1.71 (P: 0.003). Conclusion: Alteration of monocytes either on admission or within hospitalization would not provide valuable data about the prediction of COVID-19 prognosis. Although the rapidly evolving nature of COVID-19 is the major limitation of the present study, further investigations in the field of laboratory biomarkers will pave the way to manage patients with severe disease better.
ABSTRACT
Introduction: Multiple lines of evidence have attested that decreased numbers of platelets may serve as a surrogate marker for poor prognosis in a wide range of infectious diseases. Thus, to provide a well-conceptualized viewpoint demonstrating the prognostic value of thrombocytopenia in COVID-19, we performed a meta-analysis of pertinent literature. Method: The keywords "platelet" OR "thrombocytopenia" AND "COVID-19" OR "coronavirus 2019" OR "2019-nCoV" OR "SARS-CoV-2" were searched in National Library of Medicine Med-line/PubMed and Scopus between December 30, 2019, and May 9, 2020 in English without any restriction. The initial search results were first screened by title and abstract, and then full texts of relevant articles representing information on the platelet count (main outcome) with a clinically validated deïnˇA˛nition of COVID-19 severity were ïnˇA˛nally selected. To assess the existence of bias in the included studies, the funnel plot and egger plot along with egger tests were used. Also, the heterogeneity among the included studies was tested using the Chi-square test. Results: The results of our meta-analysis of 19 studies, totaling 3383 COVID-19 patients with 744 (21.9%) severe cases, revealed that non-severe cases have a significantly higher number of platelets and showed that the probability of the emergence of thrombocytopenia is significantly higher in the severe cases with the pooled mean difference of -21.5 (%95 CI: -31.57, -11.43). Conclusion: Decreased number of platelets more commonly associates with severe COVID-19;however, whether the emergence of thrombocytopenia may result in diseases severity or the severity of the disease may decrease platelets, is open to debate.
ABSTRACT
Background and Objectives: The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which was first de-scribed during a pneumonia outbreak in Wuhan, has attracted tremendous attention in a short period of time as the death toll and the number of confirmed cases is growing unceasingly. Although molecular testing is the gold standard method of SARS-CoV-2 detection, the existence of the false-negative results presents a major limitation to this method. Materials and Methods: This retrospective Double-Centre study was conducted on 1320 COVID-19 patients recruited at Taleghani and Shohadae Tajrish Hospitals in Tehran, Iran. We analyzed the leukocyte, lymphocyte and neutrophil counts of hospitalized cases both on admission and at discharge. We also evaluated the alteration of these parameters within a sev-en-day follow-up. Results: Of the whole, 1077 (81.6%) neither were admitted to intensive care unit (ICU) nor experienced death, and were defined as the mild-moderate group. Of 243 severe cases, while 59 (24.3%) were admitted to ICU and cured with the intensive care services, 184 (75.7%) patients died of the disease, either with or without ICU admission. Calculation of neu-trophil-to-lymphocyte ratio (NLR) revealed that the mild-moderate cases had a lower ratio at discharge. On the other hand, the ratio was significantly higher in the death group as compared to the ICU group;highlighting the fact that patients with a higher degree of neutrophilia and a greater level of lymphopenia have a poor prognosis. Conclusion: We suggest that NLR greater than 6.5 may reflect the progression of the disease towards an unfavorable clinical outcome, with this notion that the ratios higher than 9 may strongly result in death.
ABSTRACT
Background: Although by comparing the number of deaths to the total number of cases one may conclude that most of the infected cases are recovering, taking a look at the increasing statistics of deaths shows that SARS-CoV-2 continues to take its toll. Since lymphocytes are the main immune cells battling with rapidly evolving viruses, it comes as no surprise to assume that a decreased number of these propitious soldiers may contribute to poor prognosis of the wide range of viral infections, including COVID-19. Methods: To provide a better prospect representing the prognostic value of lymphopenia in COVID-19, we searched the national library of medicine Medline/PubMed and performed a meta-analysis of pertinent literature representing information on the lymphocyte count in COVID-19 patients. Results: The results of our meta-analysis revealed that the number of lymphocytes retains a specific clinical and biological significance in this infection and lymphopenia is seemingly an important hematological abnormality that contributes to mirror the evolution toward an unfavorable outcome. Conclusion: The rapidly evolving nature of COVID-19 together with relentless disclosure of novel findings denotes a major limitation to the current study, and further investigations in the field of prognostic biomarkers will definitively pave the way to better manage patients with severe COVID-19.
ABSTRACT
Background: Coronavirus disease 2019 (abbreviated as COVID-19) is a mysterious respiratory syndrome symptomatically spanning from healthy carriers to patients with life-threatening complications, in some cases, leading to a mournful death. For the time being, the contributory role of hematologists is much more recognized in the management of COVID-19, since the emergence of coagulopathy has recently been the focus of many studies in SARS-CoV-2 infection. Methods: To provide a well-conceptualized viewpoint demonstrating the prognostic value of coagulation-related laboratory tests, we planned to perform a meta-analysis of pertinent literature representing information on PT, aPTT, and D-dimer tests in patients with COVID-19. Results: Albeit the estimated pooled means of PT and aPTT were higher in severe cases, their mean values were not significantly higher as compared with patients in a non-severe condition. On the other hand, the mean value of D-dimer in severe patients was significantly higher than non-severe cases (X2=6.34, P=0.01), highlighting that the elevation of this parameter may be associated with the progression of the disease toward an unfavorable clinical outcome. Conclusion: Even though at the time of writing this article the lack of adequate and appropriate studies denotes a major limitation to the current study, planning for the future research to determine the prognostic value of laboratory tests reflecting SARS-CoV-2-induced coagulopathy, mainly D-dimer, will definitively cast a flash of light on the significance of therapeutic anticoagulation at least for those with no absolute contraindication.