Angiotensin-converting enzyme gene I/D polymorphism in Pakistani systemic lupus erythematosus patients

Angiotensin-converting enzyme (ACE) was first identified as a key component of the rennin-angiotensin system, as its main role is to process angiotensin I to angiotensin II and degrade bradykinin. Human ACE maps to chromosome 17q23 spans 21Kb, includes 26 exons and 25 introns. In humans, ID, DD, and II  polymorphism is located in intron 16 of the angiotensin gene. The purpose of this study is to investigate the frequency of ACE gene insertion/deletion (I/D)  polymorphism genotype in systemic lupus  erythematosus (SLE) patients and to study the correlation between I/D polymorphism of the ACE gene and clinical  manifestations of SLE. Sixty one (61) controls and 61 SLE patients were recruited from Punjab-Pakistan. Sixty one SLE patients and 61 control subjects were  studied for ACE I/D  polymorphism by using Triple primer method with nested polymerase chain reaction (PCR). The frequency of DD, ID and II genotypes was 54, 3 and 4% in SLE patients’ and 23, 32 and 6% in healthy controls, respectively. The frequency of DD allele in SLE patients with lupus nephritis is 100%, Sjogren’s syndrome 100%, Raynaud’s phenomenon 88.88%, and with rheumatoid arthritis it is 78.94%. The frequency of ID allele in SLE patients with Raynaud’s  phenomenon is 5.55%, and with rheumatoid arthritis it is 10.52%. The frequency of II allele in SLE patients with Raynaud’s phenomenon 5.55%, rheumatoid  arthritis is 10.52% but the important thing to note is that the frequency of II allele in SLE patients with vasculitis is 100%. This study was undertaken to determine whether DD, ID and II polymorphisms of Intron16 of the ACE gene is associated with SLE and whether the results support such an association. It can be concluded that lupus nephritis, Sjogren’s syndrome, Raynaud’s phenomenon, rheumatoid arthritis and vasculitis, which are common among Pakistani SLE patients, are  related diseases and ACE gene is involved in lupus  susceptibility.Key words: Systemic lupus erythematosus, angiotensin converting enzyme I/D polymorphism,  Sjogren’s syndrome, Raynaud’s phenomenon, rheumatoid  arthritis, vasculitis

Evaluation of prognostic risk models for postoperative pulmonary complications in adult patients undergoing major abdominal surgery: a systematic review and international external validation cohort study

Background Stratifying risk of postoperative pulmonary complications after major abdominal surgery allows clinicians to modify risk through targeted interventions and enhanced monitoring. In this study, we aimed to identify and validate prognostic models against a new consensus definition of postoperative pulmonary complications. Methods We did a systematic review and international external validation cohort study. The systematic review was done in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We searched MEDLINE and Embase on March 1, 2020, for articles published in English that reported on risk prediction models for postoperative pulmonary complications following abdominal surgery. External validation of existing models was done within a prospective international cohort study of adult patients (≥18 years) undergoing major abdominal surgery. Data were collected between Jan 1, 2019, and April 30, 2019, in the UK, Ireland, and Australia. Discriminative ability and prognostic accuracy summary statistics were compared between models for the 30-day postoperative pulmonary complication rate as defined by the Standardised Endpoints in Perioperative Medicine Core Outcome Measures in Perioperative and Anaesthetic Care (StEP-COMPAC). Model performance was compared using the area under the receiver operating characteristic curve (AUROCC). Findings In total, we identified 2903 records from our literature search; of which, 2514 (86·6%) unique records were screened, 121 (4·8%) of 2514 full texts were assessed for eligibility, and 29 unique prognostic models were identified. Nine (31·0%) of 29 models had score development reported only, 19 (65·5%) had undergone internal validation, and only four (13·8%) had been externally validated. Data to validate six eligible models were collected in the international external validation cohort study. Data from 11 591 patients were available, with an overall postoperative pulmonary complication rate of 7·8% (n=903). None of the six models showed good discrimination (defined as AUROCC ≥0·70) for identifying postoperative pulmonary complications, with the Assess Respiratory Risk in Surgical Patients in Catalonia score showing the best discrimination (AUROCC 0·700 [95% CI 0·683–0·717]). Interpretation In the pre-COVID-19 pandemic data, variability in the risk of pulmonary complications (StEP-COMPAC definition) following major abdominal surgery was poorly described by existing prognostication tools. To improve surgical safety during the COVID-19 pandemic recovery and beyond, novel risk stratification tools are required. Funding British Journal of Surgery Society