Impact of the COVID-19 pandemic on the incidence of surgical site infection after orthopaedic surgery: an interrupted time series analysis of the nationwide surveillance database in Japan.

BACKGROUND: During the COVID-19 pandemic, hygiene awareness was increased in communities and hospitals. However, there is controversy regarding whether such circumstances affected the incidence of surgical site infections (SSIs) in the orthopaedic surgical field. AIM: To examine the impact of the COVID-19 pandemic on the incidence of SSIs after orthopaedic surgery. METHODS: The medical records of patients having undergone orthopaedic surgery were extracted from the nationwide surveillance database in Japan. The primary outcomes were the monthly incidences of total SSIs, deep or organ/space SSIs, and SSIs due to meticillin-resistant Staphylococcus aureus (MRSA). Interrupted time series analysis was conducted between pre-pandemic (January 2017 to March 2020) and pandemic (April 2020 to June 2021) periods. RESULTS: A total of 309,341 operations were included. Interrupted time series analysis adjusted for seasonality showed no significant changes in the incidence of total SSIs (rate ratio 0.94 and 95% confidence interval 0.98-1.02), deep or organ/space SSIs (0.91, 0.72-1.15), or SSIs due to MRSA (1.07, 0.68-1.68) along with no remarkable slope changes in any parameter (1.00, 0.98-1.02; 1.00, 0.97-1.02; and 0.98, 0.93-1.03, respectively). CONCLUSIONS: Awareness and measures against the COVID-19 pandemic did not markedly influence the incidence of total SSIs, deep or organ/space SSIs, or SSIs due to MRSA following orthopaedic surgery in Japan.

The correlation of urinary podocytes and podocalyxin with histological features of lupus nephritis.

Objectives The objective of this study was to test the correlation of urinary podocyte number (U-Pod) and urinary podocalyxin levels (U-PCX) with histology of lupus nephritis. Methods This was an observational, cross-sectional study. Sixty-four patients were enrolled: 40 with lupus nephritis and 24 without lupus nephritis (12 lupus nephritis patients in complete remission and 12 systemic lupus erythematosus patients without lupus nephritis). Urine samples were collected before initiating treatment. U-Pod was determined by counting podocalyxin-positive cells, and U-PCX was measured by sandwich ELISA, normalized to urinary creatinine levels (U-Pod/Cr, U-PCX/Cr). Results Lupus nephritis patients showed significantly higher U-Pod/Cr and U-PCX/Cr compared with patients without lupus nephritis. U-Pod/Cr was high in proliferative lupus nephritis (class III±V/IV±V), especially in pure class IV (4.57 (2.02-16.75)), but low in pure class V (0.30 (0.00-0.71)). U-Pod/Cr showed a positive correlation with activity index ( r=0.50, P=0.0012) and was independently associated with cellular crescent formation. In contrast, U-PCX/Cr was high in both proliferative and membranous lupus nephritis. Receiver operating characteristic analysis revealed significant correlation of U-Pod/Cr with pure class IV, class IV±V and cellular crescent formation, and the combined values of U-Pod/Cr and U-PCX/Cr were shown to be associated with pure class V. Conclusions U-Pod/Cr and U-PCX/Cr correlate with histological features of lupus nephritis.

Neonatal Fc receptor for IgG (FcRn) expressed in the gastric epithelium regulates bacterial infection in mice.

Neonatal Fc receptors for immunoglobulin (Ig)G (FcRn) assume a central role in regulating host IgG levels and IgG transport across polarized epithelial barriers. We have attempted to elucidate the contribution of FcRn in controlling Helicobacter infection in the stomach. C57BL/6J wild-type or FcRn(-/-) mice were infected with Helicobacter heilmannii, and gastric lesions, bacterial load and the levels of antigen-specific IgG in serum and gastric juice were analyzed. The elevated levels of anti-H. heimannii IgG in gastric juice were observed exclusively in wild-type mice but not in FcRn(-/-) mice. In contrast, an increase in lymphoid follicles and bacterial loads along with deeper gastric epithelium invasion were noted in FcRn(-/-) mice. C57BL/6J wild-type or FcRn(-/-) mice were also infected with Helicobacter pylori SS1, and the results of the bacterial load in stomachs of these mice and the anti-H. pylori IgG levels in serum and gastric juice were similar to those from H. heilmannii infection. Our data suggest that FcRn can be functionally expressed in the stomach, which is involved in transcytosis of IgG, and prevent colonization by H. heilmannii and the associated pathological consequences of infection.

Validation study of the Japanese version of the Faecal Incontinence Quality of Life Scale.

AIM: The aim of the present study was to conduct a psychometric validation of the Japanese version of the FIQL (JFIQL). METHOD: A retrospective analysis of data from the JFIQL was conducted. Wexner scores and Faecal Incontinence Severity Index (FISI) scores were collected prospectively in patients with faecal incontinence who visited our centre between 2008 and 2009. For convergent validity, the JFIQL scores were compared with stages on the Wexner scale for lifestyle alteration. To evaluate reliability, Cronbach's alpha was calculated for internal consistency, whereas a test-retest study was performed to evaluate reproducibility. In assessing responsiveness, JFIQL scores before and after treatments were compared in patients whose FISI scores decreased by ≥ 50%. RESULTS: Convergent validity and internal consistency were determined in 70 patients (49 women; median age 68.5 years). The JFIQL scores were significantly associated with lifestyle alteration stages on the Wexner scale, demonstrating convergent validity in all four domains and the generic score. Cronbach's alpha was > 0.7 for generic scores and all domains except Embarrassment. The intraclass correlations for the 27 patients available for the test-retest study were > 0.7 for generic scores and all domains except Embarrassment. The median JFIQL score improved significantly after treatment in the 23 patients whose FISI scores decreased ≥ 50%, indicating good responsiveness in all four domains and the generic score. CONCLUSION: The JFIQL has been validated and is now ready for use in evaluating the symptom-specific quality of life in Japanese patients with faecal incontinence.

Pinguecula and contact lenses.

PURPOSE: To assess the relationship between age and the incidence and severity (determined by a grading system) of pinguecula in contact lens (CL) wearers, and to compare the grade of pinguecula between CL wearers and non-wearers. METHODS: A total of 600 CL wearers (94 wore hard CLs (HCLs) and 506 wore soft CLs (SCLs)) aged 11-60 years and 579 non-wearers aged 10-60 years were enrolled. The age, gender, medical history, ocular history, and grade of pinguecula at two locations (nasal and temporal) were determined in all subjects. RESULTS: There was an age-related increase in the grade of pinguecula among both CL wearers and non-wearers. The grade of pinguecula at the temporal conjunctiva was higher in CL wearers than in non-wearers (P=0.01907), whereas it was higher in HCL wearers than SCL wearers at both the nasal and temporal conjunctiva (P<0.00001 and P<0.00001). CONCLUSIONS: This was the first assessment of the severity of pinguecula in a large consecutive series of CL wearers. Our results suggest that the use of CLs is an important risk factor for pinguecula.

Detection of umbilical venous constriction by Doppler flow measurement at midgestation.

OBJECTIVES: To investigate whether umbilical venous velocity and venous velocity pulsation are associated with umbilical vein diameter, umbilical ring diameter and umbilical cord coiling index at midgestation. METHODS: Two hundred and eighty pregnant women were enrolled in the study at between 18 and 24 weeks of gestation. The diameter of the umbilical cord and internal diameter of the umbilical vein in a free loop and at the ring, and the umbilical coiling index, were measured using ultrasonography. Umbilical venous velocities were measured by Doppler ultrasonography at the umbilical ring and a free loop of the cord. RESULTS: All variables were successfully measured in 92% of the patients. There were negative correlations between the diameters of the umbilical ring and of the umbilical vein at the ring and the venous velocity at the umbilical ring. The venous velocity at the umbilical ring was significantly higher and the umbilical ring diameter was significantly lower in fetuses with umbilical venous pulsation at the free loop. Significant correlations were observed between the venous velocity and amplitude of pulsation. Venous pulsations at the free loop were frequently observed in fetuses with a hypercoiled cord. CONCLUSION: High venous velocity and increased venous pulsation at the umbilical ring may be associated with umbilical cord constriction.

Predisposing factors for massive hemorrhage during Cesarean section in patients with placenta previa.

OBJECTIVES: To investigate whether maternal history and ultrasound findings can be predictors for massive hemorrhage during Cesarean section in patients with placenta previa and adherence of the placenta. METHODS: We reviewed 127 singleton pregnancies with placenta previa. Maternal history, antenatal ultrasound findings of the placenta, including location, presence of placental lacunae, lack of a clear zone, presence of sponge-like findings of the cervix and presence of a marginal sinus in cases of placenta previa were reviewed retrospectively, and their association with amount of bleeding during Cesarean section was analyzed. RESULTS: Logistic regression analysis revealed that advanced maternal age (odds ratio (OR), 5.4; 95% CI, 1.8-16.4), previous Cesarean section (OR, 20.4; 95% CI, 4.0-105.2) and sponge-like findings in the cervix (OR, 5.6; 95% CI, 1.8-17.0) were associated with massive bleeding (> 2500 mL). Placental adherence occurred in five cases and was more frequent in cases where the placenta was located at the site of the scar of a previous Cesarean section (OR, 123.1; 95% CI, 4.5-3395.2) and where there was lack of a clear zone (OR, 48.0; 95% CI, 3.8-604.7). CONCLUSIONS: Advanced maternal age, previous Cesarean section and presence of sponge-like findings in the cervix are risk factors for massive bleeding during Cesarean section in cases of placenta previa, regardless of whether placental adherence is present. Placental location on the scar of a previous Cesarean section and lack of a clear zone are risk factors for placental adherence. When these findings are identified preoperatively, management should be tailored accordingly.

Macular microcirculation and macular oedema in branch retinal vein occlusion.

BACKGROUND/AIMS: The relationship between the blood-flow velocity in the perifoveal capillaries and macular oedema was investigated in patients with branch retinal vein occlusion (BRVO). METHODS: This study compared 18 patients with BRVO and 16 healthy volunteers. Perifoveal capillary blood-flow velocity was measured on fluorescein angiograms with a scanning laser ophthalmoscope by the tracing method. Retinal thickness at the central fovea was measured by optical coherence tomography. Then, the relation between perifoveal capillary blood-flow velocity and retinal thickness at the central fovea was investigated. RESULTS: Perifoveal capillary blood-flow velocity was significantly lower in the patients with BRVO (1.08 (SD 0.28) mm/s) than in the healthy volunteers (1.49 (0.11) mm/s) (p<0.0001). Capillary blood-flow velocity showed a negative correlation with the retinal thickness at the central fovea in the two groups (r = -0.8426, p<0.0001). Multivariate linear regression analysis with stepwise variable selection confirmed that capillary blood-flow velocity was an independent determinant of the retinal thickness at the central fovea (p<0.001). CONCLUSION: A reduction in perifoveal capillary blood-flow velocity may be involved in the development of macular oedema in patients with BRVO.

Relationship between refraction and allergic conjunctivitis.

PURPOSE: External allergens are the main causative factor in the pathogenesis of allergic diseases; however, little is known about internal factors such as the biometrical structure of the eye. We investigated the relationship between refractive error and allergic conjunctivitis in order to reveal possible insights into the pathogenesis in 1015 subjects. METHODS: The patients were divided into four groups: contact lens wearers with allergic conjunctivitis (n=73), contact lens wearers without allergic conjunctivitis (n=59), non-contact lens wearers with allergic conjunctivitis (n=224), and non-contact lens wearers without allergic conjunctivitis (n=659). The spherical power, cylindrical power, corneal radius, and minimum and maximum corneal refractive powers were measured in all subjects. RESULTS: In the non-contact lens wearers, the spherical equivalent and spherical power were significantly lower in patients with allergic conjunctivitis than in patients without allergic conjunctivitis (-3.01+/-3.83 D vs-1.36+/-3.08 D, P<0.0001, and -2.64+/-3.63 D vs-1.05+/-2.88 D, P<0.0001, respectively), while there was no significant difference in any of the parameters between the contact lens wearers with and without allergic conjunctivitis. CONCLUSION: Refractive error may be a risk factor for allergic conjunctivitis.

Changes of vascular endothelial growth factor after vitrectomy for macular edema secondary to retinal vein occlusion.

PURPOSE: To examine whether vitrectomy combined with retinal photocoagulation reduces the vitreous level of vascular endothelial growth factor (VEGF) in patients with macular edema associated with retinal vein occlusion (RVO). METHODS: The authors measured VEGF levels in vitreous samples from four eyes of four patients with RVO during vitrectomy and fluid samples obtained during revitrectomy 3 to 9 months postoperatively for complications: an epiretinal membrane in two patients, macular holes in one patient, and vitreous hemorrhage in one patient. During vitrectomy, retinal photocoagulation was performed on the ischemic region of the retina in all cases (mean of 510 shots). RESULTS: In four eyes with RVO, there was a difference in the vitreous VEGF levels between the vitreous samples obtained during vitrectomy (mean of 2692 pg/mL, range of 15.6-9040 pg/mL) and the fluid samples obtained at the time of revitrectomy (mean of 947 pg/mL, range of 15.6-3430 pg/mL). CONCLUSIONS: The results suggest that the vitreous levels of VEGF may be reduced by vitrectomy combined with retinal photocoagulation for macular edema with RVO. It may be important to reduce the vitreous levels of VEGF by vitrectomy and retinal photocoagulation for ischemic retina in macular edema with RVO.

A novel exogenous concentration-gradient collagen scaffold augments full-thickness articular cartilage repair.

OBJECTIVES: A collagen scaffold has been long used in order to enhance the regeneration of articular cartilage. In the present study, we investigate the effectiveness of a concentration-gradient (CG) collagen that is designed to recruit efficiently the mesenchymal stem cells (MSCs) to the central region of the full-thickness cartilage defects via haptotaxis. METHODS: The present study used Cellmatrix (0.3% type I collagen; Nitta gelatin, Osaka, Japan) as the collagen material. We prepared 33%CG collagen gel and 50%CG collagen gel. No gradient collagen gel served as negative control. Full-thickness cartilage defects were created at the patella groove of the rabbit knee, to which the three different collagen gels were transplanted. Bromodeoxyuridine (BrdU) positive, proliferating cells were enumerated and localized, whereas the histological grading score for cartilage regeneration was counted. The expression of type I and type II collagens was evaluated by immunohistochemistry. We also confirmed that the MSCs migrate toward the collagen substrate of higher concentration in a stringently in vitro haptotactic manner. RESULTS: Enumeration of the BrdU-positive cells demonstrated that 33%CG collagen gel recruited a significantly larger number of proliferating cells to the central region of the cartilage defect. The histological grading score for the regenerated cartilage treated with 33%CG collagen gel was superior to the other groups. CONCLUSIONS: CG collagen scaffold recruits effectively the MSCs to the center of full-thickness cartilage defect and enhances regeneration of the full-thickness cartilage defect.

Vascular compliance is secured under angiotensin inhibition in non-diabetic chronic kidney diseases.

Cardiovascular diseases constitute major cause of death in chronic kidney diseases (CKDs). We examined the effects of angiotensin inhibition either with angiotensin-converting enzyme inhibitor or with angiotensin receptor blocker on patient prognosis and heart-ankle pulse wave velocity (haPWV) in CKDs. Randomized controlled study was performed on 102 patients with non-diabetic CKDs. Patients were divided into two groups with or without angiotensin inhibition, and followed until death, creatinine clearance was halved or starting renal replacement therapy, whichever occurred first. For 4 years, haPWV was assessed repeatedly in the surviving patients. While both groups showed well blood pressure control throughout 4 years (129+/-1 to 131+/-2/71+/-1 to 73+/-2 mm Hg), renal prognosis was better in angiotensin inhibition group (P<0.05). In addition, angiotensin inhibition reduced cardiovascular and renal death (P<0.05). Age, sex, heart rate, systolic blood pressure and proteinuria were correlated to haPWV (R(2)=0.76, P<0.0001). Although haPWV was similar between two groups at the start of the study (1098+/-31 vs 1094+/-37 cm/s), it was higher in patients without angiotensin inhibition than that with angiotensin inhibition 4 years later (1034+/-38 cm/s (n=28) vs 1242+/-37 cm/s (n=23), P<0.01). The present results provided the evidence that angiotensin inhibition arrested a time-dependent elevation of haPWV in non-diabetic CKDs, conferring organ protection. Furthermore, our data indicated that angiotensin inhibition improved patient prognosis in non-diabetic chronic kidney diseases with mild-to-moderate renal dysfunction.

Aqueous humour levels of cytokines are correlated to vitreous levels and severity of macular oedema in branch retinal vein occlusion.

AIM: To investigate whether the aqueous levels of vascular endothelial growth factor (VEGF) and interleukin-6 (IL-6) are correlated to the vitreous levels of these substances and to the severity of macular oedema in branch retinal vein occlusion (BRVO). METHODS: Aqueous and vitreous samples were obtained during cataract and vitreous surgery from 24 patients (24 eyes) with macular oedema in BRVO. The VEGF and IL-6 levels in aqueous humour, vitreous fluid, and plasma were determined by enzyme-linked immunosorbent assay. The degree of retinal ischaemia was evaluated in terms of the area of capillary nonperfusion using the Scion Image. The severity of macular oedema was evaluated using the OCT. RESULTS: The aqueous level of VEGF was significantly correlated with the vitreous level of VEGF (P<0.0001). Vitreous levels of VEGF and IL-6 were significantly correlated with the nonperfusion area of BRVO (P<0.0001, P=0.0061, respectively), as were the aqueous levels of VEGF and IL-6 (P<0.0001, P=0.0267, respectively). Furthermore, the vitreous levels of VEGF and IL-6 and the aqueous level of VEGF were significantly correlated with the severity of macular oedema of BRVO (P=0.0001, P=0.0331, P=0.0272, respectively). CONCLUSION: Our results suggest that the aqueous level of VEGF may reflect its vitreous level. Measurement of the aqueous level of VEGF may be clinically useful to indicate the severity of macular oedema with BRVO.

Risk evaluation of outcome of vitreous surgery based on vitreous levels of cytokines.

AIM: To ascertain whether vitreous and plasma levels of vascular endothelial growth factor (VEGF), interleukin-6 (IL-6) and fundus findings could predict the outcome of vitreous surgery in patients with proliferative diabetic retinopathy (PDR). METHODS: Vitreous fluid samples were obtained during vitreoretinal surgery from 73 consecutive eyes with PDR. The levels of VEGF and IL-6 in vitreous fluid and plasma were determined by enzyme-linked immunosorbent assay. Patients were prospectively followed for 6 months and the postoperative outcome was analysed by logistic regression analysis. RESULTS: No improvement and/or progression of PDR occurred in 23 (32%) of the 73 eyes (progression group). The vitreous levels of VEGF and IL-6 were significantly higher in eyes from the progression group than in eyes with regression of PDR (regression group) (P=0.0032 and 0.0088, respectively). Multivariate logistic regression analysis showed that higher vitreous levels of VEGF were associated with the progression of PDR after vitreous surgery (odds ratio 2.72, P=0.0003). CONCLUSIONS: High vitreous levels of VEGF identified as a significant risk factor for the outcome of vitreous surgery in patients with PDR. A model was developed to predict the probability of PDR progression and measurement of the vitreous level of VEGF may be useful for predicting the outcome of surgery.

Bacterial and fungal microbiota in relation to probiotic therapy (VSL#3) in pouchitis.

BACKGROUND: The intestinal microbiota plays a critical role in the pathophysiology of pouchitis, a major complication after ileal pouch anal anastomosis in patients with ulcerative colitis. Recently, controlled trials have demonstrated that probiotics are effective in maintenance of remission in pouchitis patients. However, the mechanism by which therapy with probiotics works remains elusive. This study explores the role of the bacterial and fungal flora in a controlled trial for maintenance of remission in pouchitis patients with the probiotic VSL#3 compound. METHODS: The mucosa associated pouch microbiota was investigated before and after therapy with VSL#3 by analysis of endoscopic biopsies using ribosomal DNA/RNA based community fingerprint analysis, clone libraries, real time polymerase chain reaction (PCR), and fluorescence in situ hybridisation. Patients were recruited from a placebo controlled remission maintenance trial with VSL#3. RESULTS: Patients who developed pouchitis while treated with placebo had low bacterial and high fungal diversity. Bacterial diversity was increased and fungal diversity was reduced in patients in remission maintained with VSL#3 (p = 0.001). Real time PCR experiments demonstrated that VSL#3 increased the total number of bacterial cells (p = 0.002) and modified the spectrum of bacteria towards anaerobic species. Taxa specific clone libraries for Lactobacilli and Bifidobacteria showed that the richness and spectrum of these bacteria were altered under probiotic therapy. CONCLUSIONS: Probiotic therapy with VSL#3 increases the total number of intestinal bacterial cells as well as the richness and diversity of the bacterial microbiota, especially the anaerobic flora. The diversity of the fungal flora is repressed. Restoration of the integrity of a "protective" intestinal mucosa related microbiota could therefore be a potential mechanism of probiotic bacteria in inflammatory barrier diseases of the lower gastrointestinal tract.

Intratumoural expression of thymidylate synthase is an independent predictor of prognosis in patients with squamous cell carcinoma of the tongue: results from a retrospective study.

The aim of this study was to assess the importance of immunohistochemical thymidylate synthase (TS) expression level as a prognostic marker in tongue cancer patients. In 140 patients with primary squamous cell carcinoma (SCC) of the tongue, intratumoural TS expression was evaluated by immunohistochemistry. The level of TS expression was determined by a semiquantitative scoring system, ranging from 1+ to 3+ according to the ratio of TS-positive cells. Of 140 patients, 64 (45.7%), 49 (35.0%) and 27 (19.3%) were assessed as 1+, 2+ and 3+, respectively. Univariate analyses demonstrated that both disease-free survival (DFS) and overall survival (OS) were significantly lower in patients with a TS 3+ tumour than in those with a TS 1+/2+ tumour (DFS: P = 0.0082, OS: P = 0.0100). In a multivariate analysis using the Cox regression model, cervical lymph-node status and TS expression level were selected as independent factors for DFS and OS. Maintenance adjuvant chemotherapy by oral 5-fluorouracil (5-FU) significantly improved DFS and OS in patients with a TS 1+/2+ tumour (DFS: P = 0.0027, OS: P = 0.0398). These data suggest that the level of immunohistochemical TS expression is an independent prognosticator in patients with tongue SCC, and may be useful in the selection of patients who would benefit from oral 5-FU adjuvant chemotherapy.