MERS-Cov spread across the Middle East, causing human illness via solitary cases, community clusters, and nosocomial outbreaks. This retrospective research showed a link between an elevated serum LDH level and death in MERS-CoV patients. According to ROC analysis, serum LDH levels of > 512 throughout the illness were 94% sensitive and 93% specific for death and were linked with the deceased group [1 (2.7%) vs. 17 (85.0%), p = 0.001)]. The Cox proportional hazard model showed that increased serum loge (LDH) levels during admission days were an independent predictor of MERS-CoV severity and mortality (adjusted HR: 9.91, 95% CI: 2.44–40.3, p = 0.001). We observed that individuals with higher chest radiographic scores (adjusted HR: 1.24, 95% CI: 1.05–1.47, p = 0.01) were more likely to have a fatal outcome, as shown by the Cox proportional hazards model.
Although deceased individuals had a significantly higher mean age (54.37 ± 16.68, p = 0.001), age was not a risk factor after adjusting for other multivariate cox regression analysis factors (adjusted HR: 0.99, 95% CI: 0.95–1.03; p = 0.60). Our present observation was contrary to previous experience that older age is associated with increased risk of mortality in MERS-CoV patients [17]. One reason our deceased cohort's mean age was lower (54.37 ± 16.68, p = 0.001) than in previous series with higher range of mortality [17]. Ahmed et al. found that patients aged ≥ 60 years had a significantly higher death rate (45.2 percent vs 20.0 percent; p = 0.001) when compared to patients aged < 60 years [18]. Diabetes mellitus (adjusted HR: 1.01, 95% CI: 0.24–4.24, p = 0.99) and chest radiographic score (adjusted HR: 1.24, 95% CI: 1.05–1.47, p = 0.01) were risk factors that could be interpreted as increasing the likelihood that the problem will deteriorate further and exacerbate the burden of the current condition. Similarly, after adjusting for other relevant factors, it was found that LN (Log Natural) LDH was a very significant risk factor for mortality (adjusted HR: 9.91, 95% CI: 2.44–40.30, p = 0.001). Increased ventilation days are rated as protective in multivariate cox regression analysis (adjusted HR: 0.84, 95% CI: 0.76–0.93, p = 0.001), which can be interpreted to mean that an increase in ventilation days may confer resilience to patients undergoing critical care, decreasing the likelihood of a fatal outcome.
According to Assiri et al., 49% of their MERS-CoV patients exhibited increased LDH levels, compared to 50%–71% of global SARS-CoV-1 cases; however, no particular level was noted in MERS-CoV patients who died [15]. Ghamadi et al. found that 62.7 percent of their MERS-CoV patient groups had increased LDH > 300 U/L, with 56.3 percent surviving and 43% dying [19]. They have not referred to a cut-off point between survivors and those who have died. Serum LDH levels > 512 were 94% sensitive and 93% specific for disease-related death in our population. A recent pandemic of SARS-CoV-2, a SARS-CoV-2 virus that resembles MERS-CoV, has also been associated with substantially increased LDH levels [20]. Chang et al. discovered that a serum LDH cut-off value of 359.50 U/L accurately predicted SARS-CoV-2 mortality with 93.8% specificity and 88.2% accuracy [20]. Higher LDH levels were an independent risk factor for SARS-CoV-2 severity (adjusted HR: 2.73, 95% CI: 1.25–5.97, p = 0.012) and mortality (adjusted HR: 40.50, 95% CI: 3.65–449.28, p = 0.003) according to logistic regression analysis and the Cox proportional hazards model [20]. We do not know why MERS-CoV and SARS-CoV-2 have different ROC values, but we believe MERS-CoV has a greater fatality rate and more severe respiratory symptoms than SARS-CoV-2 [21, 22]. SARS-CoV-2, SARS-CoV-1, and MERS-CoV are linked with a mortality rate of 6.76%, 9.6%, and 35.5%, respectively [21, 22].
In our current series, the chest radiography score for the deceased group was considerably higher (13 ± 2.6 5 vs.8 ± 5.6, p = 0.001) than for the recovered group. Significant inverse relationships between radiography scores and SaO2 have been reported [7, 23]. All patients with diffuse consolidation required extra ventilation days [7]. We discovered a strong correlation between the chest radiographic score and the number of ventilation days in our current sample (r = 0.44, p = 0.001).
Although SARS-CoV-2, SARS-CoV-1, and MERS-CoV all frequently infect the liver, various complicating variables may skew the interpretation of existing data about the association between infection and hepatocyte damage [24]. The serum aminotransferases AST and ALT are two of the most critical enzymes for diagnosing liver illness or injury. The AST level is less specific for the liver than for the ALT level. Duan et al. reported that about 38% of SARS-CoV-1 patients exhibited elevated ALT activity, with higher levels linked to more severe disease [25]. The average increase in ALT and AST activity was 3 xULN and 1.5 xULN, respectively, in MERS patients [10]. Increased ALT and AST levels were seen in 3xULN and 8xULN of the present cohort of deceased MERS-CoV patients, respectively. We do not know what is driving our population's disproportionate rise in AST. Increased AST levels, but not ALT levels, were significantly higher in people with SARS-CoV-2 who had gastrointestinal symptoms than in those who did not (29.35 vs. 24.4, p = 0.02) [24]. We did not associate the hematological markers with the clinical presentation of the patients in this group.
Notably, the chest radiographic characteristics of 99 patients were previously reported in four separate studies [5, 26,27,28] focusing solely on the radiological aspects of MERS-CoV pneumonia in chest radiographs, from which 57 cases with LDH levels were selected for the present study. Therefore, the present study examines the relationship between laboratory parameters and chest radiographic score in MERS-CoV pneumonia patients to determine if LDH is associated with increased mortality risk.