Middle East Respiratory Syndrome Coronavirus Infection Dynamics and Antibody Responses among Clinically Diverse Patients, Saudi Arabia.

Middle East respiratory syndrome coronavirus (MERS-CoV) shedding and antibody responses are not fully understood, particularly in relation to underlying medical conditions, clinical manifestations, and mortality. We enrolled MERS-CoV-positive patients at a hospital in Saudi Arabia and periodically collected specimens from multiple sites for real-time reverse transcription PCR and serologic testing. We conducted interviews and chart abstractions to collect clinical, epidemiologic, and laboratory information. We found that diabetes mellitus among survivors was associated with prolonged MERS-CoV RNA detection in the respiratory tract. Among case-patients who died, development of robust neutralizing serum antibody responses during the second and third week of illness was not sufficient for patient recovery or virus clearance. Fever and cough among mildly ill patients typically aligned with RNA detection in the upper respiratory tract; RNA levels peaked during the first week of illness. These findings should be considered in the development of infection control policies, vaccines, and antibody therapeutics.

Beyond Frontiers: Feasibility and Outcomes of Prolonged Veno-Venous Extracorporeal Membrane Oxygenation in Severe Acute Respiratory Distress Syndrome.

Extracorporeal membrane oxygenation (ECMO) use in acute respiratory failure is increasing. We aim to compare characteristics and outcomes of patients with prolonged (≥21 days) veno-venous (VV) ECMO runs (pECMO), to patients with short (<21 days) VV ECMO runs (sECMO). The observational retrospective single-center study compared patients who received VV ECMO from January 2018 to June 2019 at Prince Mohamed Bin Abdulaziz Center in Riyadh, Saudi Arabia. Forty-three patients were supported with VV ECMO during the study period, of whom 37 are included as six patients were still receiving ECMO at time of data collection: 24 sECMO and 13 pECMO patients. Baseline characteristics and comorbidities were similar except pECMO patients were older and had a lower P/F ratio (61 [58-68] vs. 71[58-85.5], p = 0.05). Survival to hospital discharge (69% vs. 83%, p = 0.32; pECMO vs. sECMO) and 90 day survival (62% vs. 75%, p = 0.413; pECMO vs. sECMO) were similar among groups. At 1 year follow-up, all patients were still alive and independently functioning except for one patient in the pECMO group who required a walking aid related to trauma. In this single-center study, patients requiring pECMO had similar short- and long-term survival to those requiring sECMO duration.

Predictors of MERS-CoV infection: A large case control study of patients presenting with ILI at a MERS-CoV referral hospital in Saudi Arabia.

BACKGROUND: A case control study to better characterize the clinical features, laboratory, and radiological abnormalities associated with MERS-CoV infection in order to help with early identification of this syndrome from other respiratory infections. METHODS: Eighty patients admitted to a hospital in Riyadh, diagnosed with MERS-CoV infection based on RT-PCR were matched on age, sex, and the presence of a co-morbid condition on a basis of 1:2 to other patients admitted with respiratory symptoms and tested negative for MERS-CoV on RT-PCR. RESULTS: None of the reported MERS-CoV presenting symptoms was significantly associated with being infected with MERS-CoV. On the other hand, WBC count was significantly lower in patients with confirmed MERS-CoV infection (median 5.7 vs 9.3, P: 0.0004). Neutrophil count was as well significantly lower in MERS-CoV patients (median 3.7 vs 6.7, P: 0.0001). Both AST, and ALT values were significantly higher in MERS-CoV infected group (AST median 42 vs 36, P: 0.03, and ALT median 33 vs 28, P: 0.003). Overall our MERS-CoV mortality rate was (10%) below the national figure of (40%). CONCLUSIONS: None of the presenting symptoms are specific for MERS-CoV infection. And out of all the investigations WBC, neutrophil counts, AST and ALT values have some predictive utility.

The clinical role of central venous pressure measurements.

Central venous pressure (CVP) is commonly measured, but its clinical use is still not clear. We argue that the interpretation of the CVP needs to be considered in conjunction with an assessment of cardiac output. The objective of this study was to define an elevated CVP as one in which there is a low probability for cardiac output to increase with a volume infusion through a Starling mechanism by relating the initial CVP (measured relative to a reference point 5 cm below the sternal angle) to the response in cardiac output with volume infusion. The authors studied consecutive patients who had pulmonary artery catheters in place and who had a volume challenge as part of routine management as ordered by the treating physician. To ensure an adequate test of the Starling mechanism, data were included only if the volume infusion increased CVP by > or = 2 mm Hg. Responders were defined a priori as those with an increase in cardiac index > or = 300 and nonresponders as < 300 mL/min/m2. Patients failed to respond to volume infusion at all CVP values, and even 25% of those with CVP < 5 mm Hg were nonresponders. However, when CVP was > 10 mm Hg, physicians prescribed less fluid challenges, and when they did, a positive response was much less likely. Change in blood pressure or changes in urine output with volume infusion correlated poorly with change in cardiac index. A CVP of > 10 mm Hg should be considered high, and the probability of an increase in cardiac output with volume infusion is low. This value is a reasonable upper limit for algorithms for empiric fluid challenges.