BackgroundAntituberculosis (anti-TB) drug allergy often involves multiple concurrently administered drugs which subsequently need to be reinitiated as no better alternatives exist.ObjectiveTo describe the results of tailored sequential desensitization-rechallenge (D-R) for anti-TB drug allergy.MethodsConsecutive patients who had undergone D-R to anti-TB drugs between 1 September 1997 and 31 January 2012 were recruited. Following resolution of the acute reaction, anti-TB drug was restarted at 1:6,000 to 1:3 of the final daily dose (FDD), with gradual single or multiple step daily dose escalation to the FDD. Subsequent drugs were sequentially added ≥3 days later when the preceding drug was tolerated. Full blood count and liver function tests were monitored prior to addition of each new drug.ResultsThere were 11 patients of whom 10 were male, predominantly Chinese (8 patients). Regimens comprised at least 3 drugs: isoniazid (INH), rifampicin (RIF), ethambutol (EMB), pyrazinamide (PZA), or streptomycin. All patients had nonimmediate reactions, with cutaneous eruptions, where maculopapular exanthema (MPE) was the most common (8 patients). Drug-induced hypersensitivity syndrome (DIHS) occurred in 6 patients, and Stevens Johnson syndrome (SJS) in 2 patients. D-R to INH was successful in 7/9 patients (77.8%) and to RIF/EMB/PZA/streptomycin in all. Of the 2 patients who failed INH D-R, 1 developed fever and MPE on day 3, the other MPE on day 8. D-R with INH and RIF respectively was successful in 2 patients with SJS. Among DIHS patients, 1 failed D-R with INH (fever and MPE on day 3). There were 23/25 (92%) successful D-R among the 11 patients. All patients completed TB treatment of ≥5 months' duration with no cases of drug-resistant TB.ConclusionTailored sequential TB drug D-R is successful where no better alternative therapies are available, with careful dose escalation and close monitoring, and after a careful risk-benefit assessment.

BackgroundAll Singaporean males undergo medical screening prior to compulsory military service. A history of possible food allergy may require referral to a specialist Allergy clinic to ensure that special dietary needs can be taken into account during field training and deployment.ObjectiveTo study the pattern of food allergy among pre-enlistees who were referred to a specialist allergy clinic to work up suspected food allergy.MethodsRetrospective study of all pre-enlistees registered in the Clinical Immunology/Allergy New Case Registry referred to the Allergy Clinic from 1 August 2015 to 31 May 2016 for suspected food allergy.ResultsOne hundred twenty pre-enlistees reporting food allergy symptoms other than rash alone were referred to the Allergy Clinic during the study period. Of these, 77 (64.2%) had food allergy. Among those with food allergy, mean age was 19.1 ± 1.5 years. They comprised predominantly Chinese (66.2%) and Malays (20.8%). The most commonly reported foods were shellfish/crustaceans (78%), peanut (15.6%), and egg (6.5%). Self-limiting oral allergy syndrome, OAS (itchy lips and throat with/without lip angioedema) was the most common manifestation (n = 33, 42.9%) followed by anaphylaxis (n = 23, 29.9%). Majority of OAS was from shellfish/crustacean (90.6%); of which shrimp (30.3%), crab (15.2%), and lobster (3.0%) were the most common. Mild childhood asthma (69.7%), allergic rhinitis (6.3%), and eczema (6.1%) were the most common atopic conditions among individuals with shellfish/crustacean OAS. This pattern was similar for shellfish/crustacean anaphylaxis. Skin prick tests were most commonly positive for shrimp (OAS 87.1% vs. anaphylaxis 100%), crab (OAS 95.8% vs. 90.9%), and lobster (OAS 91.7% vs. 63.6%).ConclusionOAS to shellfish/crustaceans was more common than anaphylaxis among this study population of young males referred for food allergy symptoms other than rash alone.

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During the initial rollout of coronavirus disease 2019 (COVID-19) vaccination in Singapore, the Ministry of Health (MOH) issued a recommendation that patients with a history of any previous vaccine allergy be referred to an allergist for further review of their suitability to proceed with mRNA-based COVID-19 vaccines. Patients fulfilling the above criterion were divided into three groups: immediate reaction (Group A), delayed reaction (Group B) and no/irrelevant reaction (Group C). They were subjected to either a skin prick test (SPT) and intradermal test (IDT) with polyethylene glycol (PEG) or polysorbate-containing products; direct injection with the Pfizer BNT162b2 vaccine in the allergy clinic; or injection at community vaccination centres, respectively. Groups A and B were also invited to complete a questionnaire survey on post-vaccination reactions, and blood sampling pre-vaccination and 1 h after the first dose of the BNT162b2 vaccine to measure immunoglobulin (Ig) G, IgM and IgE antibodies to the Pfizer BNT162b2 vaccine via ELISA assays immobilised with the BNT162b2 vaccine, as well as levels of allergic cytokines interleukin (IL)-4 and IL-33, complement C5a and the endothelial activation marker intercellular adhesion molecule-1 (ICAM-1). Groups A and B comprised 62 (20.5%) patients each. In Group A, two subjects (3.2%) with equivocal IDT results tolerated both doses of the BNT162b2 vaccine without major allergic reactions. The remaining 60 (96.8%) in Group A and 62 (100%) in Group B completed both doses of BNT162b2 vaccination without major adverse reactions. Among the 99 who completed the questionnaire survey, 13 (13%) patients reported mild allergic reactions after the first dose of the vaccine. Immunoglobulin (Ig) G and M antibodies, but not IgE antibodies to the Pfizer BNT162b2 vaccine were detected in 67 subjects prior to vaccination. The presence of anti-Pfizer BNT162b2 IgG and IgM prior to vaccination did not result in major allergic reactions nor increases in Th2-related cytokines (IL-4, IL-33), complement activation products (C5a) or endothelial activation (ICAM-1). The majority of those with suspected reactions to non-COVID-19 polysorbate-containing vaccines tolerated the BNT162b2 vaccine. Excipient skin tests for PEG and polysorbate prior to vaccination are unnecessary.

Purpose: Portal venous gas (PVG) in neonates is a special abdominal imaging, which often indicates the occurrence of intestinal ischemia and necrosis, and is also an indicator to evaluate the severity and surgical timing of neonatal necrotizing enterocolitis. The timely identification and intervention of intestinal necrosis in neonates with PVG is particularly important, but it is still difficult at present. Various inflammatory factors in predicting prognosis and surgery timing have been described in adult literature, but rarely in neonatal literature. Therefore, we investigate the value of inflammatory factors in predicting intestinal necrosis in neonates with PVG.Methods: We retrospectively reviewed the medical records of neonates with PVG detected by ultrasound in a tertiary-level referral hospital from January 2020 to December 2020. During the study period, 168 neonates with ultrasonographically identified PVG were included and were divided into two groups according to the presence of intestinal necrosis: a necrotic group (n=35) and a non-necrotic group(n=133). We evaluated the predictive values of various combination of inflammatory markers in preoperative period laboratory analyses using the receiver operating characteristic (ROC) method. Results: In the current cohort, a total of 168 patients were identified. Of these, 35 patients (20.8%) underwent intestinal resection due to intestinal necrosis and 5 patients (3.0%) developed intestinal stricture after medical management. The overall survival rate was 164/168 (97.6%). In patients with intestinal necrosis, platelet count (p<0.001), lymphocyte count(p<0.001), Eosinophil count(p<0.001), CRP (C-reactive protein, p<0.001), PLR (platelet–lymphocyte ratio, p=0.002), NLR (neutrophil–lymphocyte ratio, p=0.001), LCR (lymphocyte–CRP ratio, p<0.001) and PCR (platelet- CRP ratio, p<0.001) values were significantly different with those in the patients without intestinal necrosis. Receiver operating characteristic (ROC) analysis results showed that the combination of C-reactive protein levels along with lymphocyte count (LCR) had the highest correlation with intestinal necrosis in neonates with portal venous gas [AUC 0.86 (95% CI 0.79–0.94); p<0.001], with sensitivity of 0.81(0.73–0.87) and specificity of 0.86(0.69–0.95) for the diagnosis of intestinal necrosis. Conclusions: The preoperative LCR score is a promising indicator for predicting intestinal necrosis in neonates with PVG, which could be used as an additional criterion to guide surgical management.

Objective This article develops a nomogram to estimate intestinal necrosis risk in the incarcerated inguinal hernia (IIH) in infants under 6 months. Methods A total of 273 infants who underwent an emergency operation due to IIH were investigated retrospectively. Univariate and multivariate logistic regression were used to analyze the relationship between variables and intestinal necrosis and construct a nomogram of intestinal necrosis. The discrimination and concordance of the model were verified by receiver operating characteristic (ROC) analysis and calibration curve, and the bootstrap method was used for internal validation of the model. The clinical applicability of the model was evaluated using the decision curve and the clinical impact curve. Results Intestinal necrosis was found in 37 of 273 infants (13.6%) in this study. The vomiting symptoms, platelet count, C-reactive protein, and neutrophil-lymphocyte ratio were independent risk factors for intestinal necrosis in IIH. We then constructed a nomogram with these four factors. ROC analysis showed that the nomogram had a good diagnostic performance, with the area under the curve (AUC), sensitivity, and specificity of 0.918 (95% confidence interval: 0.880–0.956), 97.3%, and 69.9%, respectively. The nomogram was further validated using 2,000-repetition internal bootstrap validation, and the values of AUC, sensitivity, and specificity were 0.899, 95.7%, and 50.5%, respectively. The decision curve and the clinical impact curve indicated that the predictive model has a favorable clinical application. Conclusion The nomogram can be used to predict intestinal necrosis in IIH, and allow us to estimate the severity of IIH more accurately and arrange the treatment process more reasonably.

Purpose Summarize the clinical features of neonatal gastric perforation and establish a nomogram model to predict the risk factors of early mortality after laparotomy in neonatal gastric perforation (NGP) from a tertiary care unit. Methods Retrospective analysis was performed on NGP diagnosed in our hospital between May 2003 and October 2021. All patients underwent laparotomy, and according to the prognosis, they were divided into non-survival and survival groups. All clinical characteristics, preoperative laboratory features, intraoperative situation and outcomes were collected from electronic medical records. We conducted logistic regression analyses to identify the independent factors that contribute to early neonatal death after laparotomy and the nomogram prediction model was constructed. Results A total of 111 patients with NGP were included in our study, the mortality was 23.42% (26/111). Six independent mortality risk factors were identified: APTT(OR,1.015;95% CI,1.001,1.138;p = 0.039), PaO2 (OR,0.977;95%CI,0.957,0.997;p = 0.022), Hco3−(OR,0.777;95%CI,0.616,0.979;p = 0.032),PLT(OR,0.989;95%CI,0.979,0.998;p = 0.022), SPC(OR,2.693;95%CI,1.221,5.942;p = 0.014), Combined with NEC (OR,0.040; 95% CI,0.004,0.421 ; p = 0.007). A nomogram model was constructed based independent prognostic risk factors, and its AUC under ROC curve was 0.886(95%CI,0.806,0.965;P = 0.000), which had a good degree of discrimination. Patients who had a nomogram score of more than 178.548 was considered to take high risks of mortality, and the sensitivity and specificity of identifying postoperative NGP mortality were 91.8% and 76.9%. The correction curves evaluation results showed a high consistency of the model. Conclusion APTT, PaO2, Hco3−,PLT,SPC and combined with NEC change, are independently associated with an increased risk of early mortality in neonates with neonatal gastric perforation after laparotomy. The nomogram model constructed in this study can be used as a tool to predict the risk of mortality, predict postoperative survival, and help to develop an individualized treatment plan.

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