Laboratory Findings of COVID-19 Infection are Conflicting in Different Age Groups and Pregnant Women: A Literature Review

Abstract

Coronavirus disease 2019 , a new type and rapidly spread viral pneumonia, is now producing an outbreak of pandemic proportions. The clinical features and laboratory results of different age groups are different due to the general susceptibility of the disease. The laboratory findings of COVID-19 in pregnant women are also conflicting. Para-clinical investigations including laboratory tests and radiologic findings play an important role in early diagnosis and treatment monitoring of severe acute respiratory syndrome and coronavirus-2 (SARS-CoV-2). The majority of previous reports on the SARS-CoV-2 laboratory results were based on data from the general population and limited information is available based on age difference and pregnancy status. This review aimed to describe the COVID-19 laboratory findings in neonates, children, adults, elderly and pregnant women altogether for the first time.The most attracting and reliable markers of COVID-19 in patients were: normal C-reactive protein (CRP) and very different and conflicting laboratory results regardless of clinical symptoms in neonates, normal or temporary elevated CRP, conflicting WBC count results and procalcitonin elevation in children, lymphopenia and elevated lactate dehydrogenase (LDH) in adult patients, lymphopenia and elevated CRP and LDH in the elderly people and high CRP, leukocytosis and elevated neutrophil ratio in pregnant women.

The role of cytokine profile and lymphocyte subsets in the severity of coronavirus disease 2019 (COVID-19): A systematic review and meta-analysis

“…It may be due to the direct contribution of the virus or redistribution of WBC via chemotaxis or apoptosis [ 16 , 41 , 60 ]. Compared to non-severe ones, severe cases are older and have comorbidity diseases [ [61] , [62] , [63] ], making them more susceptible to endothelial dysfunction and its associated lymphopenia. The fact that the present study showed elevated leukocyte levels in severe compared to non-severe patients across 42 studies is a novel and controversial finding.…”

“…One of the main causes might be the poor description of the analytical performance features of the methods applied among the included studies. Furthermore, aging as a condition related to the inflammation was the basis of the previous studies [ 62 , 71 ], showing that severe patients were older than non-severe ones. Since the proinflammatory response is believed to initiate SARS-CoV-2 infection, it is logically possible that the aged cases have an overwhelming inflammatory reaction.…”

Laboratory features of severe vs. non-severe COVID-19 patients in Asian populations: a systematic review and meta-analysis

“…Apart from the clinical symptoms and pulmonary computed tomography (CT) findings, a large number of COVID-19 confirmed patients showed laboratory fluctuations including complete blood count (CBC) variables, cardiac and coagulation parameters, renal and liver function tests, and inflammation-related factors [ 7 , 8 ].…”

Laboratory features in severe vs. non-severe COVID-19 patients, a systematic review and meta-analysis

“…Apart from the clinical symptoms and pulmonary computed tomography (CT) findings, a large number of COVID-19 confirmed patients showed laboratory fluctuations including complete blood count (CBC) variables, cardiac and coagulation parameters, renal and liver function tests, and inflammation-related factors (6,7).…”