Hypoxia induces senescence of bone marrow mesenchymal stem cells via altered gut microbiota.

Systemic chronic hypoxia is a feature of many diseases and may influence the communication between bone marrow (BM) and gut microbiota. Here we analyse patients with cyanotic congenital heart disease (CCHD) who are experiencing chronic hypoxia and characterize the association between bone marrow mesenchymal stem cells (BMSCs) and gut microbiome under systemic hypoxia. We observe premature senescence of BMSCs and abnormal D-galactose accumulation in patients with CCHD. The hypoxia that these patients experience results in an altered diversity of gut microbial communities, with a remarkable decrease in the number of Lactobacilli and a noticeable reduction in the amount of enzyme-degraded D-galactose. Replenishing chronic hypoxic rats with Lactobacillus reduced the accumulation of D-galactose and restored the deficient BMSCs. Together, our findings show that chronic hypoxia predisposes BMSCs to premature senescence, which may be due to gut dysbiosis and thus induced D-galactose accumulation.

Laryngeal tuberculosis: a rare cause of critical airway obstruction.

Laryngeal tuberculosis (TB) is a rare condition, occurring in less than 1% of patients infected with pulmonary TB. We present a case of a 57-year-old male patient, who presented in extremis with audible stridor, increased work of breathing and cyanosis. In addition, the patient had a complex medical history, including a recent diagnosis of congenital malformation of the epiglottis. Emergency intervention was required to secure the airway, and after initial attempts at intubation were unsuccessful, an emergency tracheostomy was performed. Four days after initial presentation, his sputum tested positive for acid-fast bacilli, and a subsequent CT chest revealed pulmonary as well as laryngeal TB, which was confirmed on biopsy of the larynx. The patient was commenced on a 24-week course of anti-tuberculous treatment and was successfully decannulated 6 months after the emergency airway was established.

Pertussis requiring intensive care.

OBJECTIVES: To describe children with pertussis who require intensive care. DESIGN, SETTING AND PATIENTS: An audit in Auckland, New Zealand, of pertussis admissions to the national paediatric intensive care unit (PICU) from 1991 to 2003. RESULTS: 72 children, 97% of whom were <12 months old. The annual number of cases increased with time (p = 0.04). Forty patients (56%) were coughing for less than 8 days before admission. Apnoea or paroxysmal cough was present in 33 (83%) of these children. Thirty five (49%) received assisted ventilation. Four died. 19% were readmitted to PICU. Those readmitted presented with more atypical disease and had a shorter first admission but longer total PICU admission (9 vs 5 days, p = 0.009). Of the 58 children from Auckland, nine either died (three) or had subsequent respiratory or neurodevelopmental problems (six). There was an increased risk (relative risk, 95% CI) of death or disability associated with having a co-morbidity (RR = 5.56, 1.50 to 8.15), an elevated lymphocyte count (RR = 5.75, 1.54 to 13.65), presenting with seizures/encephalopathy (4.87, 1.18 to 8.34) or shock (6.50, 1.89 to 8.94), having a PIM score of 1% or more (RR = 6.20, 1.22 to 21.72), any abnormal neurological signs (RR = 9.65, 3.32 to 15.23) or being readmitted to PICU (RR = 4.63, 1.44 to 8.82). CONCLUSIONS: Apnoea and paroxysmal cough are key symptoms of pertussis in those with shorter cough duration. Death or disability are frequent. Clinical factors define children at increased risk of these poor outcomes. Early discharge from PICU is associated with an increased risk of readmission and poor outcome.

Bacteriological and histological profile of turkeys condemned for cyanosis.

Canadian Food Inspection Agency (CFIA) has adopted the term cyanosis to describe a category of condemnation for poultry that is dark but has no other condemnable lesions. Two case-control studies (n = 30 pairs; n = 65 pairs) of 18-wk-old tom turkeys were conducted. A case was defined as a carcass condemned by the veterinary inspector for cyanosis, and a control carcass was one that passed inspection. Microbiological tests were conducted on samples of Pectoralis major and Gastrocnemius lacteralis. A modified Rappaport Vassiliadis medium was used for Salmonella, and a Petrifilm method was used to assess aerobic counts, coliform counts, and Escherichia coli. The Salmonella (qualitative) test was negative for all cases and controls, and there were no significant differences between the aerobic counts, coliform counts, and E. coli counts of case and control carcasses. Two pathologists conducted a blind histopathological study: there were no lesions compatible with those of septicemia-toxemia, as defined by CFIA and the USDA, nor any significant histopathological differences between the skin, P. major, G. lateralis, kidney, liver, spleen, small intestine, pancreas, lung, and heart of cases and controls. The inter-rater agreement between pathologists ranged from good to excellent (Kappa = 0.7 to 1.0). In the absence of important lesions and microbial contamination, carcasses with this color change alone should be suitable for human consumption.

Increased susceptibility to gingival colonization by specific HACEK microbes in children with congenital heart disease.

It is well established that infective endocarditis (IE) involving the HACEK (Hemophilus, Actinobacillus, Cardiobacter, Eikenella, Kingella) group of microbes occurs in patients with congenital heart defects (CHD) and in those with prosthetic grafts. Dental caries and gingival disease have been presumed to be the focus of microbial shedding. The purpose of this study was to determine if children with CHD had a more severe gingival inflammatory condition and harbored the HACEK group of microbes to a greater extent than normal children. Two groups of 12 age and sex matched children were selected for this study. The experimental group consisted of twelve children with CHD, 1-1/2 to 8 years of age. The control group consisted of 12 healthy children 2 to 8 years of age. Each child had a gingival index score recorded as described by Massler. Subgingival cultures were obtained. Gingival samples were cultured for HACEK microbes and total Streptococcus (spp) using standard techniques. Fisher's exact test was performed with significance defined at P < 0.05. Children with CHD had more severe gingival inflammatory index than the control group (P < 0.05). 8/12 CHD patient had Actinobacillus actinomycetemcomitans (A.a.) as compared with 2/12 controls (P < 0.05). Furthermore, all cyanotic CHD patients (4/4) had A.a. whereas, only 2/12 controls did (P < 0.05). 4/12 CHD patients harbored Eikenella corrodens (E.c.) compared to 1/12 controls (N.S.). There was no significant difference in colonization with E.c. or A.a. between cyanotic and acyanotic patients. No significant difference in total Streptococcus (spp) was found between the two groups. This study suggests that children with CHD have a more severe gingival inflammatory index and are colonized with specific HACEK microbes more so than normal children.

A new prognostic scoring system in neonatal tetanus.

A prospective study of 75 cases of neonatal tetanus was carried out with a view to developing a prognostic scoring system which can be used to assess the severity of the disease and to serve as a basis for comparing results of different therapeutic interventions from various centres. The case fatality rate was 77.3%. A table was designed containing 6 parameters and a rating of 1 to 4 was given to each parameter in decreasing order of severity. The minimum total score attainable was 6 and the maximum 24 (the severity of the disease was inversely proportional to the score). The differences between the means of each of the parameters among patients who died and the survivors were significant (P < 0.005). Regression analysis showed that each of the parameters independently had a significant effect on the total score (P < 0.005). Using the percentage mortality at each score, a pattern emerged such that total scores of 6-11 indicated severe tetanus (mortality rate 100%); 12-17, moderate disease (mortality rate 68%), and total scores of > 17 indicated mild neonatal tetanus (mortality rate 18%). Associated poor prognostic factors identified included pneumonia, recurrent apnoea, cyanosis, and opisthotonus.