Hematology and Culture Assessment of Cranially Implanted Rhesus Macaques (Macaca mulatta)

The use of percutaneous cranial implants in rhesus macaques (Macaca mulatta) has long been a valuable tool for neuroscience research. However, when treating and assessing these animals, veterinarians are required to make assumptions about diagnostic results due to a lack of research into how these implants affect physiology. Microbial cultures of cranial implant sites show an abundance of colonizing bacteria, but whether these microbes affect animal health and wellbeing is poorly understood. In addition, microbial antibiotic resistance can present significant health concerns for both the animals and the researchers. To help elucidate the relationship between percutaneous cranial implants and blood parameters, complete blood cell counts and serum chemistry results were assessed on 57 nonhuman primates at our institution from September 2001 to March 2017. Generalized estimating equations were used to compare the results before and after an animal's first implant surgery. This modelling showed that cranial implants were a significant predictor of alterations in the number of neutrophils, lymphocytes, and red blood cells, and in the concentration of hemoglobin, alkaline phosphatase, creatinine, calcium, phos- phorus, total protein, albumin, and globulin. Anaerobic and aerobic bacterial cultures were performed to identify bacteria associated with cranial implants. Staphylococcus spp., Streptococcus spp., and Corynebacterium spp. comprised the majority of the aerobic bacterial isolates, while Fusobacterium spp., Peptostreptococcus spp. and Bacterioides fragilis comprised the majority of anaerobic bacterial isolates. Using a Pearson r correlation for statistical analysis, we assessed whether any of these bacterial isolates developed antibiotic resistances over time. Cefazolin, the most frequently used antibiotic in monkeys in this study, was the only antimicrobial out of 41 agents tested to which bacteria developed resistance over time. These results indicate that percutaneous implants are associated with a generalized inflammatory state, multiple bacterial species are present at the implant site, and these bacteria may contribute to the inflammatory response.

COVID-19 in lung transplant recipients: A single center case series from New York City

There are limited data describing COVID-19 in lung transplant recipients. We performed a single center, retrospective case series study of lung transplant patients followed by the Columbia Lung Transplant program who tested positive for SARS-CoV-2 between March 19 and May 19, 2020. Thirty-two lung transplant patients developed mild (16%), moderate (44%), or severe (41%) COVID-19. The median age of patients was 65 years, and the median time from lung transplant was 5.6 years. Symptoms included cough (66%), dyspnea (50%), fever (47%), and gastrointestinal upset (44%). Patients received hydroxychloroquine (84%), azithromycin (75%), augmented steroids (44%), tocilizumab (19%), and remdesivir (9%). Eleven patients (34%) died at a median time of 14 days from admission. Complications during admission included: acute kidney injury (63%), transaminitis (31%), shock (31%), acute respiratory distress syndrome (25%), neurological events (25%), arrhythmias (22%), and venous thromboembolism (9%). Compared to patients with moderate COVID-19, patients with severe COVID-19 had higher peak white blood cell counts (15.8 vs 7 × 10³ /uL, P = .019), C-reactive protein (198 vs. 107 mg/L, P = .010) and D-dimer (8.6 vs. 2.1 ug/mL, P = .004) levels, and lower nadir lymphocyte counts (0.09 vs. 0.4 × 10³ /uL, P = .006). COVID-19 is associated with severe illness and a high mortality rate in lung transplant recipients.

Association Between Hypoxemia and Mortality in Patients With COVID-19

OBJECTIVE

To identify markers associated with in-hospital death in patients with coronavirus disease 2019 (COVID-19)-associated pneumonia.

PATIENTS AND METHODS

A retrospective cohort study was conducted of 140 patients with moderate to critical COVID-19-associated pneumonia requiring oxygen supplementation admitted to the hospital from January 28, 2020, through February 28, 2020, and followed up through March 13, 2020, in Union Hospital, Wuhan, China. Oxygen saturation (SpO2) and other measures were tested as predictors of in-hospital mortality in survival analysis.

RESULTS

Of 140 patients with COVID-19-associated pneumonia, 72 (51.4%) were men, with a median age of 60 years. Patients with SpO2 values of 90% or less were older and were more likely to be men, to have hypertension, and to present with dyspnea than those with SpO2 values greater than 90%. Overall, 36 patients (25.7%) died during hospitalization after median 14-day follow-up. Higher SpO2 levels after oxygen supplementation were associated with reduced mortality independently of age and sex (hazard ratio per 1-U SpO2, 0.93; 95% CI, 0.91 to 0.95; P<.001). The SpO2 cutoff value of 90.5% yielded 84.6% sensitivity and 97.2% specificity for prediction of survival. Dyspnea was also independently associated with death in multivariable analysis (hazard ratio, 2.60; 95% CI, 1.24 to 5.43; P=.01).

CONCLUSION

In this cohort of patients with COVID-19, hypoxemia was independently associated with in-hospital mortality. These results may help guide the clinical management of patients with severe COVID-19, particularly in settings requiring strategic allocation of limited critical care resources.

TRIAL REGISTRATION

Chictr.org.cn Identifier: ChiCTR2000030852.

Identification of a SLC19A2 nonsense mutation in Persian families with thiamine-responsive megaloblastic anemia

Thiamine-responsive megaloblastic anemia (TRMA) is an autosomal recessive syndrome characterized by early-onset anemia, diabetes, and hearing loss caused by mutations in the SLC19A2 gene. We studied the genetic cause and clinical features of this condition in patients from the Persian population. A clinical and molecular investigation was performed in four patients from three families and their healthy family members. All had the typical diagnostic criteria. The onset of hearing loss in three patients was at birth and one patient also had a stroke and seizure disorder. Thiamine treatment effectively corrected the anemia in all of our patients but did not prevent hearing loss. Diabetes was improved in one patient who presented at the age of 8months with anemia and diabetes after 2months of starting thiamine. The coding regions of SLC19A2 were sequenced in all patients. The identified mutation was tested in all members of the families. Molecular analyses identified a homozygous nonsense mutation c.697C>T (p.Gln233*) as the cause of the disease in all families. This mutation was previously reported in a Turkish patient with TRMA and is likely to be a founder mutation in the Persian population.

Association of human metapneumovirus with radiologically diagnosed community-acquired alveolar pneumonia in young children

OBJECTIVES

To determine the involvement of human metapneumovirus (HMPV) in childhood community-acquired alveolar pneumonia (CAAP) and compare the demographic, clinical, and laboratory features of HMPV-associated CAAP and CAAP associated with other respiratory viruses.

STUDY DESIGN

Nasopharyngeal wash specimens obtained prospectively over a 4-year period from children age < 5 years evaluated in the emergency department with radiologically diagnosed CAAP and from healthy controls were tested for HMPV by reverse-transcriptase polymerase chain reaction and for respiratory syncytial virus (RSV), adenovirus, influenza and parainfluenza viruses by direct immunofluorescence and culture.

RESULTS

HMPV was detected in 108 of 1296 patients (8.3%) versus RSV in 23.1%, adenovirus in 3.4%, influenza A virus in 2.9%, and parainfluenza viruse in 2.9%. During the period of peak activity (November to May), HMPV was detected in 95 of 1017 patients (9.3%) and in 3 of 136 controls (2.2%) (P = .005). The patients with HMPV were older than those with RSV (P < .001) with a more common history of acute otitis media requiring tympanocentesis (P = .032), wheezing (P = .001) and gastrointestinal symptoms (P < .001) and a lower hospitalization rate (P = .005).

CONCLUSIONS

The high detection rate suggests an important role for HMPV in childhood CAAP. Our findings identify demographic and clinical features of HMPV-positive CAAP and its age-related impact on hospital admissions.

Hematology and plasma chemistry reference intervals for mature laboratory pine voles (Microtus pinetorum) as determined by using the nonparametric rank percentile method

Plasma biochemical and hematologic values are important parameters for assessing animal health and experimental results. Although normal reference values for many rodent species have been published, there is a dearth of similar information for the genus Microtus. In addition, most studies use a mean and standard deviation to establish reference intervals, but doing so is not the recommendation of the Clinical and Laboratory Standards Institute (formerly the National Committee on Clinical Laboratory Standards) or the International Federation of Clinical Chemistry and Laboratory Medicine. The purpose of this study was to establish normal reference parameters for plasma biochemistry and hematology in mature pine voles (Microtus pinetorum) by using the nonparametric rank percentile method as recommended by the 2 laboratory medicine organizations mentioned. Samples of cardiac blood from a closed colony of pine voles were collected at euthanasia and evaluated under rodent settings on 2 automated hematology analyzers from 2 different manufacturers and on the same type of automated biochemistry analyzer. There were no sex-associated clinically significant differences between the sexes; younger animals had a lower hematocrit, higher mean corpuscular volume, and lower mean corpuscular hemoglobin concentration than did older animals. Only platelet counts differed when comparing hematologic values from different analyzers. Relative to rats and mice, pine voles have a lower mean corpuscular volume and higher red blood cell count, higher blood urea nitrogen, much higher alanine aminotransferase, and lower glucose and phosphorous concentrations. Hematology and plasma biochemical results obtained in this study are considered representative for healthy adult laboratory pine voles under similar environmental conditions.

How to interpret and pursue an abnormal complete blood cell count in adults

A complete blood cell count (CBC) is one of the most common laboratory tests in medicine. For example, at our institution alone, approximately 1800 CBCs are ordered every day, and 10% to 20% of results are reported as abnormal. Therefore, it is in every clinician's interest to have some understanding of the specific test basics as well as a structured action plan when confronted with abnormal CBC results. In this article, we provide practical diagnostic algorithms that address frequently encountered conditions associated with CBC abnormalities including anemia, thrombocytopenia, leukopenia, polycythemia, thrombocytosis, and leukocytosis. The objective is to help the nonhematologist recognize when a subspecialty consultation is reasonable and when it may be circumvented, thus allowing a cost-effective and intellectually rewarding practice.

Genetic variation in parameters reflecting immune competence of swine

Genetic variation in total and differential white blood cell (WBC) counts, phagocytic capacity of polymorphonuclear leukocytes (PMNL), virus induced interferon-alpha (IFN-alpha) production, mitogen induced proliferation and interleukin 2 (IL-2) production of mononuclear cells (MNC) in vitro was studied in blood collected from 124 Yorkshire piglets, aged 8 weeks. The piglets were the offspring from 12 sires and 31 dams. Data from an earlier experiment, including 96 piglets of seven sires and 24 dams, were added when estimating heritabilities for Con A induced proliferation and IL-2 production. The highest heritability (h2 = 0.87 +/- 0.41) was estimated for the total number of PMNL. Medium high heritabilities (h2 = 0.3-0.4) were estimated for the phagocytic capacity of PMNL, Con A induced proliferation and IL-2 production and the total number of WBC, while the heritability estimates were lower (h2 = 0.00-0.08 +/- 0.12) for the total number of lymphocytes, serum concentrations of Ig and IFN-alpha production. Pronounced differences between litters from various dams were found for total number of lymphocytes, IFN-alpha production, Con A induced proliferation and IL-2 production. The Con A induced proliferation was positively correlated (r = 0.48, P < 0.001) with the IL-2 production and both these parameters were correlated (r = 0.44 and 0.37, respectively, P < 0.001) to the virus induced IFN-alpha production. Despite these positive correlations, no parental offspring group was uniformly superior across all traits measured. However, the heritabilities estimated for the immune parameters are sufficiently high to be used as genetic markers in selection for general immune competence of swine.