Effects of oral bovine lactoferrin on a mouse model of inflammation associated colon cancer.

Patients with ulcerative colitis or colonic Crohn's disease have a significantly increased risk of developing colorectal cancer. Bovine lactoferrin (bLF) reportedly inhibited the development of colon cancer in rats and mice, and in a placebo controlled trial, ingestion of bLF inhibited the growth of intestinal polyps. In addition, in a case study, a patient with Crohn's disease was reported to have remained in remission for over 7 years while ingesting 1 g of bLF daily. Thus, bLF has an inhibitory effect on colon carcinogenesis, and it may also promote remission of Crohn's disease. The purpose of this study was to investigate the effects of bLF in a mouse model of colorectal cancer related to irritable bowel disease (IBD). The mice were divided into 4 groups: (i) no treatment; (ii) treated with bLF only; (iii) treated with azoxymethane plus dextran sulfate sodium (AOM + DSS); and (iv) treated with AOM + DSS + bLF. AOM was used to initiate intestinal cancer, and DSS was used to induce IBD-like inflammation in the intestine of the C57BL/6 mice. At the end of the study, the mice treated with AOM + DSS + bLF had a better fecal score, fewer lesions in the colon, and less weight loss than the mice treated with AOM + DSS without bLF. However, there were no statistically significant differences between the two groups with respect to tumor burden.

[Effects of drug treatment on the surviral-time in patients with dementia].

AIM: The effect of polypharmacy on the surviral-time in patients with dementia has never been fully elucidated. METHODS: A retrospective study was conducted in a hospital in Aichi, Japan, by reviewing the medical charts and autopsy reports. Patients were hospitalized and neuropathologically diagnosed with dementia. The data on medication was collected from the prescribed drugs taking right before the admission. Patients were divided into two groups according to the number of prescribed drugs: ≥ 5 drugs (polypharmacy) vs. ≤ 4 drugs (non-polypharmacy). "Drugs to be prescribed with special caution" were defined in accordance with the guidelines for medical treatment and its safety in the elderly (2015). RESULTS: Seventy-six patients were eligible, and 39.5% of patients had polypharmacy. The Kaplan-Meier method showed that the polypharmacy group tended to have a shorter survival-time than the non-polypharmacy group (p=0.067). A Cox proportional hazard model showed that the polypharmacy group tended to have a higher risk for a reduced survival-time than the non-polypharmacy group, and this tendency was more prominent after adjusting for sex and age at admission (adjusted hazard ratio, 1.631; 95% confidence interval, 0.991-2.683; p=0.054). "Drugs to be prescribed with special caution", including hypnotic-sedative drugs, antianxiety drugs, antipsychotics, and benzodiazepines, were not found to be risk factors for a reduced survival-time. CONCLUSIONS: The present study showed that polypharmacy in terminal patients with dementia tended to carry a risk for reducing their remaining lifespan. The results warrant further additional study.

[The consciousness survey and the effect of educational intervention of Advance Care Planning (ACP) including post-mortem to elderly residents living in old New Town of big city].

AIM: Awareness reform aims to enable survival in an aging society, and ultimately, improve healthcare. An ideal way to achieve this is by implementing Advance directive (Ad) and Advance Care Planning (ACP), which do not usually include postmortem events. This study aims to create opportunities for Ad and ACP to include the postmortem period as a trigger for this awareness reform. METHODS: We conducted an Ad/ACP enlightenment lecture, and a questionnaire survey pre- and post-lecture for the elderly in old New Town, which is known for its aging society. The questionnaire comprised 38 multiple-choice questions covering 6 themes assuming an advanced state of dementia. RESULTS: There were 35 participants (7 men and 22 women) aged 40-89 years. Several people left during the lecture, making it difficult to capture the precise transformation effect with regard to changing of mind. However, the effect of enlightenment was identified as a result of the consciousness survey. A statistically significant change in consciousness occurred in response to social contribution after death. Furthermore, notably more people wanted emergency transportation compared to those wanting resuscitation and extension of life. CONCLUSIONS: The medical treatment desired might vary over time. Even the desire for life extension may differ significantly among individuals. This survey indicated a divergent view between the general public and medical staff, regarding a series of medical actions. We must persistently promote opportunities for enlightenment in cooperation with the general public (i.e., the communities and families we serve).

Novel characteristics of traction force in biliary self-expandable metallic stents.

BACKGROUND AND AIM: In recent years, knowledge concerning the mechanical properties of self-expandable metallic stents (SEMS) has increased. In a previous study, we defined traction force and traction momentum and reported that these characteristics are important for optimal stent deployment. However, traction force and traction momentum were represented as relative values and were not evaluated in various conditions. The purpose of the present study was to measure traction force in various situations assumed during SEMS placement. METHODS: Traction force and traction momentum were measured in non-stricture, stricture, and angled stricture models using in-house equipment. RESULTS: Stricture and angled stricture models had significantly higher traction force and traction momentum than those of the non-stricture model (stricture vs non-stricture: traction force, 7.2 N vs 1.4 N, P < 0.001; traction momentum, 237.8 Ns vs 62.3 Ns, P = 0.001; angled stricture vs non-stricture: traction force, 7.4 N vs 1.4 N, P < 0.001; traction momentum, 307.2 Ns vs 62.3 Ns, P < 0.001). Traction force was variable during SEMS placement and was categorized into five different stages, which were similar in both the stricture and angled stricture models. CONCLUSIONS: We measured traction force and traction momentum under simulated clinical conditions and demonstrated that strictures and the angular positioning of the stent influenced the traction force. Clinicians should be aware of the transition of the traction force and should schedule X-ray imaging during SEMS placement.

Endoscopic retrograde cholangiopancreatography-related adverse events in patients with type 1 autoimmune pancreatitis.

BACKGROUND: Endoscopic retrograde cholangiopancreatography (ERCP) is frequently performed for the diagnosis and treatment of type 1 autoimmune pancreatitis (AIP). However, the prevalence of ERCP-related adverse events in patients with type 1 AIP has not been evaluated. We aimed to clarify the feasibility of ERCP in patients with type 1 AIP. METHODS: We retrospectively reviewed 82 consecutive ERCP procedures performed in patients with type 1 AIP from 2004 to 2014 in one university hospital and three tertiary-care referral centers. One hundred four ERCP procedures in chronic pancreatitis and 1123 in non-AIP cohort were enrolled as control groups. We compared the incidence of post-ERCP pancreatitis (PEP) between type 1 AIP and control groups. We evaluated the incidence of ERCP-related adverse events and various predictive factors for hyperamylasemia after ERCP. RESULTS: Pancreatography and cholangiography by ERCP were obtained in 78 (95.1%) and 76 (92.7%) patients, respectively. The incidence of PEP, cholangitis, and bleeding was 1.2% (1/82), 0%, and 1.2%, respectively. PEP occurred in type 1 AIP patient with diffuse parenchymal imaging, and the severity was mild. The incidences of PEP were 2.9% (3/104) and 5.4% (61/1123) in chronic pancreatitis and normal cohort, respectively. The incidence of PEP was slightly lower in type 1 AIP than non-AIP cohort (1.2% vs 5.8%, p = 0.119). There were no significant predictive factors for hyperamylasemia after ERCP in type 1 AIP. CONCLUSIONS: The incidence of ERCP-related adverse events is low in patients with type 1 AIP. ERCP-related procedures are feasible in the diagnosis and treatment of AIP.

Diagnosis of autoimmune pancreatitis by EUS-guided FNA using a 22-gauge needle: a prospective multicenter study.

BACKGROUND AND AIMS: Histopathologic examination is critical for diagnosing autoimmune pancreatitis (AIP). However, specimens obtained using EUS-guided FNA (EUS-FNA) are not recommended for histopathologic diagnosis because of inadequate sample size volume. We evaluated EUS-FNA efficacy for AIP diagnosis using a 22G needle. METHODS: Seventy-eight patients exhibiting the imaging characteristics indicative of AIP in the pancreatic parenchyma and pancreatic duct underwent EUS-FNA with a 22G needle at 12 institutions between February 2013 and March 2014. Samples were evaluated for tissue sampling conditions, CD38- and IgG4-positive plasma cell counts, storiform fibrosis (SF), and obliterative phlebitis (OP). RESULTS: Tissue specimens containing >10, 5 to 10, and 1 to 4 high-power fields (HPFs) were obtained from 29 (37.2%), 18 (23.1%), and 15 (19.2%) of 78 patients, respectively. The mean ± standard deviation (SD) CD38- and IgG4-positive plasma cell counts were 23.2 ± 18.8/HPF and 5.1 ± 6.7/HPF, respectively. SF was detected in 49 of 78 patients (62.8%) and OP in 38 of 78 patients (48.7%). According to the International Consensus Diagnostic Criteria (ICDC), histopathologic levels corresponded to level 1 in 32, level 2 in 13, and unclassifiable in 17 patients. Hence, 45 of 78 patients (57.7%) could be diagnosed with lymphoplasmacytic sclerosing pancreatitis according to ICDC. CONCLUSIONS: Pancreatic tissues with at least 1 HPF were obtained by EUS-FNA from approximately 80% of patients, and nearly 60% of patients were diagnosed with ICDC level 2 or higher. Our findings indicate that EUS-FNA with a 22G needle may be useful for the histopathologic diagnosis of AIP. (Clinical trial registration number: UMIN000010097.).

New concept of traction force applied to biliary self-expandable metallic stents.

BACKGROUND AND STUDY AIMS: Various mechanical properties of self-expandable metallic stents (SEMSs) have been reported. They can be classified into the device behavior during and after deployment. While there have been several reports on the latter, information on the former is insufficient. During deployment, the position is maintained by retracting the delivery catheter. We propose that this pulling force be called the traction force and that the magnitude of traction force is termed the traction momentum. The aim of this study was to measure these parameters in order to clarify the properties of SEMSs in terms of their deployment. MATERIAL AND METHODS: The traction force, traction momentum, and shortening rate of 10 different SEMSs were measured. Traction force was measured using in-house equipment, and the shortening rate was determined by measuring the stents. RESULTS: The shortening rate was closely related to the stent structure. The traction force varied between 1.5 N and 9.4 N, and the traction momentum was significantly elevated in covered and braided stents. A high traction force did not imply a high traction momentum. CONCLUSIONS: A low or constant traction force and a minimal shortening rate significantly facilitated SEMS deployment to optimal positions. Traction force could be an important element for new ideal SEMS design.

Clinical features of acute obstructive suppurative pancreatic ductitis: A retrospective review of 20 cases.

BACKGROUND AND AIMS: The clinical features of acute obstructive suppurative pancreatic ductitis (AOSPD) have not been elucidated. We aimed to clarify the clinical features of AOSPD. METHODS: We retrospectively reviewed the clinical features of 20 patients with AOSPD at two tertiary referral centers between 1993 and 2012. We compared 17 AOSPD patients with chronic pancreatitis (CP) and 42 patients with acute-on-CP in terms of clinical characteristics, presentation, and laboratory and imaging findings. RESULTS: The etiology of AOSPD involved CP in 17 (85%) patients, pancreatic ductal adenocarcinoma in 2 (10%), and intraductal papillary mucinous neoplasm in 1 (5%). Endoscopic pancreatic drainage was effective in 19 (95%) patients. Body temperature was significantly higher in AOSPD with CP than acute-on-CP patients (median: 38.2 vs 36.9 °C; P < 0.001). Serum amylase levels at onset were significantly lower (median: 133 vs 364.5 U/L; P = 0.009), and C-reactive protein was significantly higher (median: 9.42 vs 1.06 mg/dL; P < 0.001) in AOSPD with CP patients. Enlargement of the pancreatic parenchyma (18 vs 93%; P < 0.001) and stranding of the surrounding fat (12 vs 93%; P < 0.001) on computed tomography were observed less frequently in patients with AOSPD with CP patients. The diameter of the main pancreatic duct was significantly greater in AOSPD with CP than acute-on-CP patients (median: 7 vs 5 mm; P = 0.006). CONCLUSIONS: The major etiology of AOSPD involved CP, and endoscopic pancreatic drainage was effective. The clinical features differ between AOSPD with CP and acute-on-CP.

Correlation between long-term outcome and steroid therapy in type 1 autoimmune pancreatitis: relapse, malignancy and side effect of steroid.

OBJECTIVES: Autoimmune pancreatitis (AIP) responds well to corticosteroid therapy (CST), and CST is essential to induce remission. However, the correlation between long-term outcome and CST has not been evaluated. We aimed to clarify the correlation between long-term outcome of AIP and CST. MATERIAL AND METHODS: We retrospectively evaluated relapse, risk of malignancy and side effects of CST by focusing on the correlation with CST in 84 patients with type 1 AIP. RESULTS: The incidence of relapse was 23.8%. The frequency of relapse after CST administration was significantly lower in patients taking CST for >6 months than in those who did not (22% versus 67%; p = 0.036). The incidence of malignancy was 10.7%. The standardized incidence ratio of malignancy was 2.14 [95% confidence interval 0.74-3.54]. There were no significant correlations between development of malignancy and CST. The incidences of total and serious side effects due to CST were 75% and 19.1%, respectively. Relapse was the only significant independent predictive risk factor for serious side effects in a multivariate analysis (odds ratio 4.065; 95% confidence interval 1.125-14.706; p = 0.032). The cumulative dose of corticosteroid was significantly higher in patients with serious side effects than in those without (12,645 mg versus 7322 mg; p = 0.041). CONCLUSIONS: CST reduces relapse of AIP. However, CST causes serious side effects, particularly in relapsing patients. Alternative maintenance therapy to prevent relapse is needed.

Comparison of intraductal ultrasonography findings between primary sclerosing cholangitis and IgG4-related sclerosing cholangitis.

BACKGROUND AND AIM: Comparisons of intraductal ultrasonography (IDUS) findings between primary sclerosing cholangitis (PSC) and IgG4-related sclerosing cholangitis (IgG4-SC) have not been elucidated. We aimed to clarify the differences in transpapillary IDUS findings between PSC and IgG4-SC. METHODS: We retrospectively compared transpapillary IDUS findings between 15 patients with PSC and 35 patients with IgG4-SC between 2004 and 2014. RESULTS: IDUS findings of circular-asymmetric wall thickness, irregular inner margin, diverticulum-like outpouching, unclear outer margin, heterogeneous internal echo, and disappearance of three layers were significantly higher in PSC than in IgG4-SC (P < 0.001). Irregular inner margin, diverticulum-like outpouching, and disappearance of three layers were specific IDUS findings for PSC compared to IgG4-SC. Diverticulum-like outpouching on IDUS and endoscopic retrograde cholangiogram (ERC) was observed in 10 (67%) and five (33%) of 15 patients with PSC, respectively. However, based on IDUS and ERC, diverticulum-like outpouching was not observed in any patient with IgG4-SC. All five patients with diverticulum-like outpouching on ERC had diverticulum-like outpouching on IDUS, and five (50%) of 10 patients without diverticulum-like outpouching on ERC had diverticulum-like outpouching on IDUS. CONCLUSIONS: The IDUS findings differed between PSC and IgG4-SC. Irregular inner margin, diverticulum-like outpouching, and disappearance of three layers are specific IDUS findings for PSC compared to IgG4-SC. IDUS is a more useful procedure than ERC for the early detection of diverticulum-like outpouching.

Safety and benefits of self-expandable metallic stents with chemotherapy for malignant gastric outlet obstruction.

BACKGROUND AND AIM: The influence of chemotherapy on placement of self-expandable metallic stents (SEMS) for malignant gastric outlet obstruction (MGOO) has not been evaluated extensively. We investigated the influence of chemotherapy on the clinical outcomes of SEMS placement for MGOO. METHODS: A total of 152 cancer patients with MGOO from a university hospital and affiliate hospitals were included. The patients were classified according to chemotherapy status and evaluated for palliative efficacy and safety of SEMS placement. RESULTS: Technical success rate, time to oral intake, and parameters indicating improvement of physical condition did not differ between the with- and without-chemotherapy groups after stent placement. Re-intervention and stent migration were significantly more frequent in the with-chemotherapy group than in the without-chemotherapy group after stent placement (re-intervention, 32.4% vs 7.8%, P = 0.0005; stent migration, 13.5% vs 1.7%, P = 0.0097). The frequency of adverse events did not differ between the with- and without-chemotherapy groups. Although chemotherapy after stent placement was an independent predictive factor for shortening the stent patency period (hazard ratio [HR], 3.10; P = 0.0264), the use of additional stents facilitated uneventful recovery and further prolonged survival time (HR, 0.60; P = 0.0132). CONCLUSIONS: Various cancer patients with MGOO can undergo SEMS placement safely regardless of chemotherapy, and concurrent chemotherapy after stent placement can prolong survival time, although re-intervention and stent migration may be increased.

A comparison of the diagnostic efficacy in type 1 autoimmune pancreatitis based on biopsy specimens from various organs.

BACKGROUND: Comprehensive immunostaining evaluation of the biopsy specimens from various organs with type 1 autoimmune pancreatitis (AIP) has not been elucidated. Our aim was to clarify which of these biopsy specimens and counting method could be a useful tool for supporting the diagnosis of AIP. METHODS: We retrospectively evaluated biopsy specimens from pancreas (n = 19), stomach (n = 28), duodenum (n = 27), duodenal papilla (n = 25), colon (n = 19), liver (n = 11), bile duct (n = 24), and minor salivary gland (n = 13) in 36 patients with AIP. Positive IgG4 immunostaining (>10 plasma cells/high-power field [HPF]) and positive IgG4/IgG ratio (>40%) of biopsy specimens from 8 sites of 6 organs in one HPF and an average from 3 HPFs were compared between AIP and controls. RESULTS: The sensitivity of IgG4 immunostaining for AIP in one HPF were 16% in pancreas, 14% in stomach, 15% in duodenum, 52% in duodenal papilla, 11% in colon, 27% in liver, 21% in bile duct and 8% in minor salivary gland, respectively. The positive IgG4 immunostaining of the duodenal papilla in one HPF showed the highest sensitivity (52%) and accuracy (73%) among the 8 sites. It also showed the highest sensitivity among 4 different counting methods (IgG4 immunostaining in one HPF and 3 HPFs, both IgG4 immunostaining and IgG/IgG4 ratio in one HPF and 3 HPFs), but there were no significant differences with respect to specificity and accuracy. CONCLUSIONS: IgG4 immunostaining of swollen duodenal papilla with more than 10 IgG4-positive plasma cells in at least one HPF is useful for supporting the diagnosis of AIP.

Autoimmune pancreatitis presenting a short narrowing of main pancreatic duct with subsequent progression to diffuse pancreatic enlargement over 24 months; natural history of autoimmune pancreatitis.

CONTEXT: Initial pancreatogram and natural history of autoimmune pancreatitis (AIP) have not been clarified, and there were few recent studies concerning the association between AIP and intraductal papillary mucinous neoplasm (IPMN). CASE REPORT: We report an 81-year- old man with AIP associated with IPMN. Although the initial pancreatogram was normal, a short narrowing of the main pancreatic duct (MPD) appeared during a follow-up for IPMN after 6 months, which was highly suggestive of pancreatic cancer. A narrowing of the MPD extended after 15 months, and this progressed to diffuse narrowing of the MPD with an elevation in the serum IgG4 levels after 24 months. Finally, the patient was diagnosed with diffuse-type AIP, according to the Japanese diagnostic criteria 2011 and the International Consensus Diagnostic Criteria. Considering the natural history of AIP, this marked change of the MPD is indicative of this condition. CONCLUSION: We report a case of AIP presenting with a short narrowing of the MPD with subsequent progression to diffuse pancreatic enlargement during a follow-up for IPMN.

Role of endoscopy in the diagnosis of autoimmune pancreatitis and immunoglobulin G4-related sclerosing cholangitis.

Autoimmune pancreatitis (AIP) must be differentiated from pancreatic carcinoma, and immunoglobulin (Ig)G4-related sclerosing cholangitis (SC) from cholangiocarcinoma and primary sclerosing cholangitis (PSC). Pancreatographic findings such as a long narrowing of the main pancreatic duct, lack of upstream dilatation, skipped narrowed lesions, and side branches arising from the narrowed portion suggest AIP rather than pancreatic carcinoma. Cholangiographic findings for PSC, including band-like stricture, beaded or pruned-tree appearance, or diverticulum-like outpouching are rarely observed in IgG4-SC patients, whereas dilatation after a long stricture of the bile duct is common in IgG4-SC. Transpapillary biopsy for bile duct stricture is useful to rule out cholangiocarcinoma and to support the diagnosis of IgG4-SC with IgG4-immunostaining. IgG4-immunostaining of biopsy specimens from the major papilla advances a diagnosis of AIP. Contrast-enhanced endoscopic ultrasonography (EUS) and EUS elastography have the potential to predict the histological nature of the lesions. Intraductal ultrasonographic finding of wall thickening in the non-stenotic bile duct on cholangiography is useful for distinguishing IgG4-SC from cholangiocarcinoma. Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is widely used to exclude pancreatic carcinoma. To obtain adequate tissue samples for the histological diagnosis of AIP, EUS-Tru-cut biopsy or EUS-FNA using a 19-gauge needle is recommended, but EUS-FNA with a 22-gauge needle can also provide sufficient histological samples with careful sample processing after collection and rapid motion of the FNA needles within the pancreas. Validation of endoscopic imaging criteria and new techniques or devices to increase the diagnostic yield of endoscopic tissue sampling should be developed.

Predictive factors for pancreatitis and cholecystitis in endoscopic covered metal stenting for distal malignant biliary obstruction.

BACKGROUND AND AIM: Pancreatitis and cholecystitis are major complications after self-expandable metal stent (SEMS) placement in distal malignant biliary obstruction. We aimed to clarify predictive factors for pancreatitis and cholecystitis after covered SEMS placement. METHODS: We retrospectively reviewed 74 consecutive patients with distal malignant biliary obstruction who underwent initial endoscopic drainage using covered SEMS. Predictive factors for pancreatitis and cholecystitis were evaluated in the 74 patients described above and in 66 patients who had not undergone cholecystectomy. RESULTS: The incidences of pancreatitis and cholecystitis were 10.8% (8/74) and 6.1% (4/66), respectively. Univariate analysis revealed that non-pancreatic cancer (P = 0.018) and contrast injection into the pancreatic duct (P = 0.030) were significant predictive factors for pancreatitis. Multivariate analysis revealed that non-pancreatic cancer (odds ratio [OR], 4.21; 95% confidence interval [CI], 1.63-14.18; P = 0.007) and contrast injection into the pancreatic duct (OR, 3.34; 95% CI, 1.33-9.60; P = 0.016) were significant independent predictive factors for pancreatitis. On the other hand, univariate and multivariate analyses revealed that tumor involvement to the orifice of the cystic duct (OCD) was a significant independent predictive factor for cholecystitis (OR, 5.85; 95% CI, 1.91-27.74; P = 0.005). CONCLUSIONS: Non-pancreatic cancer and contrast injection into the pancreatic duct were predictive factors for pancreatitis, and tumor involvement to the OCD was a positive predictive factor for cholecystitis after endoscopic covered SEMS placement for distal malignant biliary obstruction.

Establishment of a serum IgG4 cut-off value for the differential diagnosis of IgG4-related sclerosing cholangitis: a Japanese cohort.

BACKGROUND AND AIM: IgG4-related sclerosing cholangitis (IgG4-SC) must be precisely distinguished from primary sclerosing cholangitis and cholangiocarcinoma (CC) because the treatments are completely different. However, the pathological diagnosis of IgG4-SC is difficult. Therefore, highly specific non-invasive criteria such as serum IgG4 should be established. This study established a cut-off for serum IgG4 to differentiate IgG4-SC from respective controls using serum IgG4 levels measured in Japanese centers. METHODS: A total of 344 IgG4-SC patients were enrolled in this study. As controls, 245, 110, and 149 patients with pancreatic cancer, primary sclerosing cholangitis, and CC, respectively, were enrolled. IgG4-SC patients were classified into three groups: type 1 (stenosis only in the lower part of the common bile duct), type 2 (stenosis diffusely distributed throughout the intrahepatic and extrahepatic bile ducts), and types 3 and 4 (stenosis in the hilar hepatic region) with 246, 56, and 42 patients, respectively. Serum IgG4 levels were compared, and the cut-offs were established. RESULTS: The cut-off obtained from receiver operator characteristic curves showed similar sensitivity and specificity to that of 135 mg/dL when all IgG4-SC and controls were compared. However, a new cut-off value was established when subgroups of IgG4-SC and controls were compared. A cut-off of 182 mg/dL can increase the specificity to 96.6% (4.7% increase) for distinguishing types 3 and 4 IgG4-SC from CC. A cut-off of 207 mg/dL might be useful for completely distinguishing types 3 and 4 IgG4-SC from all CC. CONCLUSIONS: Serum IgG4 is useful for the differential diagnosis of IgG4-SC and controls.

Clinical characteristics and mortality risk among critically ill patients with COVID-19 owing to the B.1.617.2 (Delta) variant in Vietnam: A retrospective observational study.

BACKGROUND: SARS-CoV-2 Delta variant caused a large number of COVID-19 cases in many countries, including Vietnam. Understanding mortality risk factors is crucial for the clinical management of severe COVID-19. METHODS: We conducted a retrospective study at an intensive care center in Ho Chi Minh City that urgently built by Bach Mai Hospital during the COVID-19 outbreak in Vietnam, when the Delta variant predominated. Participants were laboratory-confirmed patients with SARS-CoV-2 infection, admitted in August 2021. Data on patients' demographic and clinical characteristics, radiographic and laboratory findings, treatment, and clinical time course were compared between survivors and non-survivors. Risk factors to mortality were assessed using logistic regression. RESULTS: Among 504 eligible COVID-19 patients, case fatality was 52.2%. Unvaccinated patients accounted for 61.2% of non-survivors and 43.6% of survivors (p < 0.001). The time from onset to hospital admission was 8 days in non-survivors and 7 days in survivors (p = 0.004). Among non-survivors, 90.2% developed acute respiratory distress syndrome (ARDS). Oxygen therapy was administered for all patients, but antiviral agent was given to 51.7% of non-survivors. 54.2% of non-survivors tested positive for the bacterial infection using blood culture. The risk factors for mortality were diabetes mellitus, respiration rate, oxygen saturation, vaccination status, time from onset to admission, and older age. CONCLUSIONS: Critical patients with COVID-19 owing to the Delta variant in Vietnam had delayed hospital admission, leading to ARDS and death. Early availability of vaccines and preventing bacterial infections are crucial for reducing mortality of COVID-19, especially in low- and middle-income countries.