Diagnostic performance of ultrasound in acute cholecystitis: a systematic review and meta-analysis.

BACKGROUND: An updated overview of ultrasound (US) for diagnosis of acute cholecystitis (AC) remains lacking. This systematic review was conducted to evaluate the diagnostic performance of US for AC. METHODS: A systematic review was conducted following PRISMA guidelines. We meticulously screened articles from MEDLINE, Embase, and the Cochrane Library, spanning from inception to August 2023. We employed the search strategy combining the keywords "bedside US", "emergency US" or "point-of-care US" with "AC". Two reviewers independently screened the titles and abstracts of the retrieved articles to identify suitable studies. The inclusion criteria encompassed articles investigating the diagnostic performance of US for AC. Data regarding diagnostic performance, sonographers, and sonographic findings including the presence of gallstone, gallbladder (GB) wall thickness, peri-GB fluid, or sonographic Murphy sign were extracted, and a meta-analysis was executed. Case reports, editorials, and review articles were excluded, as well as studies focused on acalculous cholecystitis. The study quality was assessed with the Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) tool. RESULTS: Forty studies with 8,652 patients were included. The majority of studies had a low risk of bias and applicability concerns. US had a pooled sensitivity of 71% (95% CI, 69-72%), a specificity of 85% (95% CI, 84-86%), and an accuracy of 0.83 (95% CI, 0.82-0.83) for the diagnosis of AC. The pooled sensitivity and specificity were 71% (95% CI, 67-74%) and 92% (95% CI, 90-93%) performed by emergency physicians (EPs), 79% (95% CI, 71-85%) and 76% (95% CI, 69-81%) performed by surgeons, and 68% (95% CI 66-71%) and 87% (95% CI, 86-88%) performed by radiologists, respectively. There were no statistically significant differences among the three groups. CONCLUSION: US is a good imaging modality for the diagnosis of AC. EP-performed US has a similar diagnostic performance to radiologist-performed US. Further investigations would be needed to investigate the impact of US on expediting the management process and improving patient-centered outcomes.

Effects of COVID-19 vaccine type on Guillain-Barré syndrome: Two cases and a literature review.

Guillain-Barré syndrome (GBS) is a rare but severe complication of COVID-19 vaccination. We report two cases of GBS following vaccination with the adenovirus vector vaccine ChAdOx1 nCoV-19 (Vaxzevria, AstraZeneca) and review the relevant literature. Relevant studies published between December 2020 and May 2022 including 881 patients with GBS were reviewed. GBS incidence and the need for mechanical ventilation were reported at a higher level among patients receiving Vaxzevria (n = 400). However, incidence cannot be accurately estimated from case reports. Thus, the true GBS rates following COVID-19 vaccination should be determined by population-based data.

The outcomes of right-sided and left-sided colonic diverticulitis following non-operative management: a systematic review and meta-analysis.

BACKGROUND: There is no sufficient overview of outcomes in right-sided and left-sided colonic diverticulitis (CD) following non-operative management. This systematic review was conducted to evaluate the recurrence/treatment failure in right-sided and left-sided CD. METHODS: A systematic review was conducted following PRISMA guidelines. MEDLINE, Embase, and Cochrane Library from inception to Dec 2021 were searched. The study characteristics, recurrence/treatment failure, and risk factors for recurrence/treatment failure were extracted. Proportional meta-analyses were performed to calculate the pooled recurrent/treatment failure rate of right-sided and left-sided CD using the random effect model. Logistic regression was applied for the factors associated with the recurrence/treatment failure. RESULTS: Thirty-eight studies with 10,129 patients were included, and only two studies comprised both sides of CD. None of the studies had a high risk of bias although significant heterogeneity existed. The pooled recurrence rate was 10% (95% CI 8-13%, I2 = 86%, p < 0.01) in right-sided and 20% (95% CI 16-24%, I2 = 92%, p < 0.01) in left-sided CD. For the uncomplicated CD, the pooled recurrence rate was 9% (95% CI 6-13%, I2 = 77%, p < 0.01) in right-sided and 15% (95% CI 8-27%, I2 = 97%, p < 0.01) in the left-sided. Age and gender were not associated with the recurrence of both sides. The treatment failure rate was 5% (95% CI 2-10%, I2 = 84%, p < 0.01) in right-sided and 4% (95% CI 2-7%, I2 = 80%, p < 0.01) in left-sided CD. The risk factors for recurrence and treatment failure were limited. CONCLUSION: Non-operative management is effective with low rates of recurrence and treatment failure for both right-sided and left-sided CD although left-sided exhibits a higher recurrence. The recurrence rates did not differ between patients receiving antibiotics or not in uncomplicated CD. Age and sex were not associated with the recurrence although other risk factors were dispersing. Further risk factors for recurrence and treatment failure would be investigated for precise clinical decision-making and individualized strategy.

Birth Cohort Effects in Breast Cancer Incidence: Global Patterns and Trends.

Breast cancer is the most common neoplasm in the world among women. The age-specific incidences and onset ages vary widely between Asian and Western countries/regions. Invasive breast cancer cases among women from 1997 to 2011 were abstracted from the International Agency for Research on Cancer and the Taiwan Cancer Registry. Age-period-cohort analysis was performed to examine the trends. The cohort effect was prominent in South Korea, Taiwan, Japan, and Thailand, possibly related to the timing of westernization. The risk of breast cancer initially rose with the birth cohorts in Hong Kong and India (both former British colonies), peaked, and then declined in recent birth cohorts. Unlike other Asian countries/regions, virtually no birth cohort effect was identified in the Philippines (a Spanish colony in 1565 and the first Asian country to adopt Western cultural aspects). Moreover, an at-most negligible birth cohort effect was identified for all ethnic groups (including Asian immigrants) in the United States. This global study identified birth cohort effects in most Asian countries/regions but virtually no impact in Western countries/regions. The timing of westernization was associated with the birth cohort effect.

Severe immune thrombocytopenia following COVID-19 vaccination (Moderna) and immune checkpoint inhibitor.

Safe and effective prophylactic vaccines are urgently needed to contain the coronavirus disease 2019 (COVID-19) pandemic. However, several vaccination-related adverse effects have been reported. Here, we report a rare case of severe immune thrombocytopenia occurring 3 days after receiving the mRNA-1273 (Moderna) COVID-19 vaccine in an Asian woman with a history of refractory lung adenocarcinoma treated with durvalumab, an immune checkpoint inhibitor. Treatment with platelet transfusion (12 units) and oral prednisolone (1 mg/kg per day) significantly improved her hemoptysis with thrombocytopenia. To the best of our knowledge, this is the first case of ITP following Moderna inoculation among Asians. This study highlights a potential adverse effect of mRNA-based COVID-19 vaccines in cancer patients receiving immune checkpoint inhibitors.

Measurement of subglottic diameter and distance to pre-epiglottic space among Chinese adults.

Proper endotracheal tube (ETT) size selection and identification of potentially difficult airways are important to reduce laryngeal injury during intubation. However, controversies exist concerning transverse subglottic diameter-the narrowest part of the airway-and the distance to pre-epiglottic space. Because few studies have reported the distance from skin to the midpoint of the epiglottis (DSE) among normal individuals, whether the DSE varies between individuals and by ethnicity remains uncertain. The present study aims to investigate the sonographic subglottic diameter and DSE among healthy Chinese adults. Healthy volunteers were recruited at National Taiwan University Hospital between October and November 2019. Exclusion criteria included pre-existing airway or respiratory diseases, neck tumors, and a history of neck operation. Age, sex, height, weight, body mass index (BMI), sonographic DSE, and transverse subglottic diameter were recorded. A total of 124 participants were enrolled. The average age was 32.5 ± 10.4 years and 63 participants (51%) were males. The subglottic diameter was positively associated with sex (males, 14.40 mm; females, 11.10 mm, p < 0.001) and BMI (underweight, 12.13 mm; normal weight, 12.47 mm; overweight, 13.80 mm; obese, 13.67 mm, p = 0.007). Moreover, the DSE was shorter in males (male, 16.18 mm; females, 14.54 mm, p < 0.001) and participants with increased BMI (underweight, 13.70 mm; normal weight, 15.06 mm; overweight, 16.58 mm; obese, 18.18 mm, p < 0.001). As compared with other ethnicity, a smaller size of subglottic diameter and a shorter DSE were noted among Chinese participants, and we suggest that a relatively smaller size of endotracheal tube selection should be considered in tracheal intubations.

Adding trans-abdominal elastography to the diagnostic tool for an ileal gastrointestinal stromal tumor: a case report.

BACKGROUND: Diagnosis of gastrointestinal stromal tumors (GISTs) in the distal small intestine is difficult by endoscopic ultrasound. This is the first reported case of an ileal GIST, which is diagnosed by transabdominal sonography and strain elastography. CASE PRESENTATION: A 75 y/o woman presented with tarry stool and dizziness. No definite bleeder could be identified by esophagogastroduodenoscopy and colonoscopy. The transabdominal sonography revealed a large heterogeneous tumor involving the muscular layer of the ileum. Strain elastography showed the strain ratio was 6.51. Strain histogram was skewed to the blue side, and mean color value was 230.5, signifying a stiff tumor. GIST was highly suspected. The patient underwent laparoscope-assisted tumor excision and the histological examination confirmed a malignant GIST. The patient was discharged without postoperative event. CONCLUSION: Transabdominal strain elastography could play a role to discriminate small bowel GISTs and other submucosal tumors, especially in the location with difficulty in endoscopic ultrasound.

Long-term outcome of patients with acute cholecystitis receiving antibiotic treatment: a retrospective cohort study.

BACKGROUND: Few studies have followed patients who received antibiotic treatment for acute cholecystitis (AC). The present retrospective study investigated recurrence rates of AC and analyzed factors associated with recurrence after antibiotic treatment in adult AC patients. METHODS: We analyzed patients treated with antibiotics for AC between October 1, 2004, and November 30, 2010. A Cox proportional hazards model was used to identify factors associated with early recurrence. Generalized additive models were applied to detect the nonlinear effects of continuous covariates. RESULTS: The study included 226 patients (mean age: 62.2 years; 144 men [63.7 %]). The average duration of parenteral antibiotics was 8.0 days. Second-generation cephalosporins were administered to 199 patients (88.1 %). The Kaplan-Meier plot indicated that recurrences were more frequent within 100 days of AC; these were defined as early recurrences. The recurrence rate was 13.7 % (31/226) at a median follow-up of 308.5 days (early recurrences: 19/226 [8.4 %]). The duration of parenteral antibiotic use significantly correlated with early recurrence (hazard ratio: 0.83; 95 % confidence interval, 0.73-0.95; p = 0.005). Generalized additive models revealed that patients using parenteral antibiotics longer than 8 days were less likely to suffer from early recurrence. CONCLUSIONS: The rate of recurrence of AC in patients who received antibiotics alone was low. The recurrence rate was higher within 100 days of AC. Because of the inherent limitations of a retrospective study, further research is needed to identify factors associated with early recurrence.

Appendicolith delays resolution of appendicitis following nonoperative management.

INTRODUCTION: Success in nonoperative management is only based on the clinical symptoms of patients with acute appendicitis. However, imaging studies can provide further insight into the status of the appendix to monitor treatment response if immediate appendectomy is not undertaken. This study investigates sonographic resolution following nonoperative management and assesses the feasibility of incorporating ultrasound into patient care. MATERIALS AND METHODS: Adult patients with acute appendicitis who had been successfully treated with nonoperative management were enrolled and received repeat sonographic examinations using 3-day intervals until sonographic resolution. The relationship between the time to achieve sonographic resolution and clinical parameters was identified using negative binomial regression models. RESULTS: From January 2003 to December 2009, 128 patients were successfully treated with nonoperative management. Eighty patients completed sonographic examinations until achieving resolution. Sonographic resolution was achieved on 17 ± 12 days (range, 3-69 days). Ninety-five percent of the patients achieved sonographic resolution within 41 days. The appendicolith was positively related to the time to achieve sonographic resolution (rate ratios, 1.63; 95 % confidence intervals, 1.06-2.51). CONCLUSIONS: Ultrasound can be used to evaluate the condition of the appendix to monitor treatment response following nonoperative management on the sixth week. An appendicolith delays sonographic resolution of appendicitis.

Male gender is a risk factor for recurrent appendicitis following nonoperative treatment.

BACKGROUND: This prospective study investigates recurrence rates and identifies predictive factors for recurrence following successful nonoperative treatment in adult patients with acute appendicitis. METHODS: Between January 2003 and December 2009, adult patients with acute appendicitis who received successful nonoperative management were enrolled. Cumulative recurrence rates were calculated using the Kaplan-Meier method. Recurrence-free curves were compared using with the log-rank test. Cox regression models were employed to identify parameters that significantly and independently predict recurrence. RESULTS: During the study period, 128 patients were enrolled. The median follow-up period was 12 months (range=1-90 months). Twenty (16%) patients developed recurrent appendicitis during follow-up. Twenty-one (16%) patients underwent interval appendectomy (IA). There was no significant difference between nonperforated (NPA) and perforated appendicitis (PA) groups with respect to recurrence rates (16% at the 9th month). Moreover, male gender was significantly associated with recurrence (HR 3.45; 95% CI, 1.15-10.39). Analytical results remained significant after excluding IA patients. CONCLUSIONS: Since the recurrence rate is similar between NPA and PA, nonoperative treatment can be used for PA patients. Roughly 20% of the adult patients selected for nonoperative treatment experienced recurrence. Males were more susceptible than females to recurrent appendicitis.

Male gender and renal dysfunction are predictors of adverse outcome in nonpostoperative ischemic colitis patients.

OBJECTIVE: Ischemic colitis (IC) spans a broad spectrum from self-limiting illness to intestinal gangrene and mortality. Prognostic factors specifically for nonpostoperative IC were not fully characterized. We aim to focus on nonpostoperative IC in patients with renal dysfunction and try to identify prognostic factors for adverse outcomes. METHODS: We conducted a retrospective analysis at a university-affiliated tertiary medical center in Taiwan. From January 2003 to August 2008, 25 men and 52 women (mean age: 66 y) had colonoscopic biopsy-proven IC without prior culprit surgery. We estimated glomerular filtration rate with simplified Modification of Diet in Renal Disease equation. Nine patients with glomerular filtration rate below 30 mL per minute per 1.73 m were classified as renal dysfunction group (including 7 dialysis patients). Adverse outcomes were defined as need for surgery and mortality. Predictors for adverse outcomes were captured by univariate and multivariate analysis. Research ethical committee approved the study protocol. RESULTS: Patients with renal dysfunction more often had: diabetes mellitus (56% vs. 16%, P=0.02), prolonged symptoms (6.8 d vs. 3.5 d, P=0.01), lower hemoglobin (11.1 g/dL vs. 13.4 g/dL, P=0.01), and more often right colonic involvement (56% vs. 19%, P=0.03). Renal dysfunction patients also had longer hospitalization days (median 15 d vs. 4 d, P=0.045). However, there was no statistical significance in the rate of either surgery or mortality between these 2 groups (P>0.05). Univariate analysis showed that renal dysfunction, sex, emergency department referral, presentation with abdominal pain were significant for adverse outcome (P<0.1). Multivariate analysis revealed that male sex conveyed 9.5-fold risk (P=0.01) and renal dysfunction conveyed 8.5-fold risk (P=0.03) for adverse outcomes. CONCLUSIONS: Nonpostoperative IC patients with concurrent renal dysfunction had distinct clinical profiles. Multivariate analysis showed that male patients had 9.5-fold and renal dysfunction patients had 8.5-fold increased risk for adverse outcomes. Although IC is often self-limited, our data warrants special attention and aggressive therapy in treating these patients.

Spontaneous rupture of an ovarian artery aneurysm.

Spontaneous rupture of an ovarian artery aneurysm is rare and is thought to be related to pregnancy or uterine fibroids. A patient without fibroids presented with extreme pain during normal menstruation. Ruptured ovarian artery aneurysm should be suspected in a multiparous woman with flank or abdominal pain and peritoneal signs.

The sandwich sign of non-lymphomatous origin.

PURPOSE: To investigate the etiologies of the sandwich sign other than lymphoma. METHOD: The images of 34 patients with sonographic sandwich sign over a 5-year period were retrospectively reviewed. The etiology was based on the pathologic report of mesenteric lymph nodes, or the presence of extensive metastatic disease in case of known advanced primary cancer or disappearance of the sign after specific treatments. RESULTS: Malignancy accounted for the majority of cases (91%), and was divided into non-Hodgkin's lymphoma (50%) and metastatic carcinomas (41%). Mycobacterium tuberculosis infection was diagnosed in a previously healthy patient, and 2 patients with acquired immunodeficiency syndrome had Mycobacterium avium-complex infection. The sandwich sign was 1 of the initial presentations in 11 cases with newly diagnosed malignancies, including 6 cases of non-Hodgkin's lymphoma and 5 cases of metastatic carcinomas. CONCLUSION: Metastatic carcinomas, M. avium-complex, and M. tuberculosis infection may produce the sandwich sign. Searching for etiologies other than lymphoma is important in patients presenting with the sandwich sign.

Appendiceal outer diameter as an indicator for differentiating appendiceal mucocele from appendicitis.

BACKGROUND: Patients with appendiceal mucocele (AM) commonly present with features indicative of acute appendicitis. In emergency departments, accurate preoperative diagnosis is crucial to prompt appropriate treatment. This study investigates the clinical and sonographic characteristics of AM, which may prove useful in preoperatively differentiating AM from appendicitis. METHODS: This case-control study compares the clinical and sonographic findings of 16 histologically confirmed AM with sex- and age-matched control subjects (n = 64) with appendicitis by a 1:4 ratio. Conditional logistic regression was applied to estimate the odds ratio (OR) and 95% confidence intervals (CI) of clinical and sonographic parameters associated with AM. RESULTS: Univariate analysis demonstrated that the larger appendiceal outer diameter by sonography was positively correlated with diagnosis of AM (OR, 2.31; 95% CI, 1.42-3.72) and right lower quadrant abdominal pain was negatively correlated (OR, 0.38; 95% CI, 0.17-0.82). However, multiple regression analysis suggested that only outer diameter remained significant (OR, 2.21; 95% CI, 1.36-3.59) after adjusting for age, sex, and right lower quadrant pain. An outer diameter of 15 mm or more was predictive of AM diagnosis, with a sensitivity of 83% and specificity of 92%. CONCLUSION: When the threshold is set at 15 mm, appendiceal outer diameter by sonography is a useful preoperative measurement for differentiating between AM and acute appendicitis.

ED presentation of acute porphyria.

Abdominal pain is a common complaint for visits to ED. Among the causes of abdominal pain, the acute porphyria may confuse emergency physicians. With wide range of unspecific symptoms and signs, acute porphyria is rarely considered as a differential diagnosis of acute abdomen in ED. Some patients even receive unnecessary surgery. There are 32 patients who visited the ED of National Taiwan University Hospital because of acute porphyric attacks over the past 13 years. Ten patients (3 males and 7 females) were diagnosed with acute porphyria for the first time at ED. The onset of age ranged from 17 to 55 years (mean, 32 years). All of our patients presented with abdominal pain but without fever, dermatologic, and neurologic symptoms that are typically presented in acute porphyria. On the average, most of them repeatedly sought for medical help because of persistent symptoms for 4 times before being definitely diagnosed and thus receiving the optimal treatment. Meanwhile, all patients needed at least 2 kinds of analgesic, and most of them needed narcotic analgesia for pain control before diagnosis. The most commonest point of tenderness is over epigastrium (7 of 10 patients). The laboratory and image studies of our patients were of no diagnostic value for acute porphyria, except for Watson-Schwartz test. In summary, our study revealed that when a patient after puberty with repetitive visits because of severe abdominal pain without reasonable causes and needs narcotics for pain control, acute porphyria should be taken into consideration.