Brote nosocomial de COVID-19 en una planta de medicina interna: probable transmisión aérea / Nosocomial outbreak of COVID-19 in an internal medicine ward: Probable airborne transmission

Antecedentes y objetivos A pesar de los datos cada vez mayores que respaldan la importancia de la transmisión aérea en la infección por el SARS-CoV-2, en la inmensa mayoría de los brotes nosocomiales descritos de COVID-19 no se ha considerado relevante. El objetivo de este estudio consiste en describir un brote nosocomial de infección por el SARS-CoV-2 cuyas características indican que la transmisión por aerosoles desempeñó un papel importante. Métodos Se trata de un análisis descriptivo de un brote nosocomial de infección por el SARS-CoV-2 en una planta de medicina interna que tuvo lugar en diciembre de 2020. Todos los casos se confirmaron mediante una PCR positiva para SARS-CoV-2. Resultados Entre el 5 y el 17 de diciembre, 21 pacientes y 44 profesionales sanitarios contrajeron una infección nosocomial por el SARS-CoV-2. De los 65 casos, 51 (78,5%) se diagnosticaron entre el 6 y el 9 de diciembre. La tasa de afectación en los pacientes fue del 80,8%. Entre los profesionales sanitarios, la tasa fue mayor en los que habían trabajado al menos una jornada laboral completa en la planta (56,3%) que en los que habían estado ocasionalmente en ella (25,8%; p=0,005). Tres días antes de detectar el primer caso positivo se identificó una avería en 2extractores de aire, que afectó a la ventilación de 3habitaciones. Dieciséis casos cursaron de forma asintomática, 48 manifestaron síntomas leves y 2 precisaron ingreso en la unidad de cuidados intensivos. Todos los casos se recuperaron finalmente. Conclusiones La elevada tasa de afectación, la naturaleza explosiva del brote y la coincidencia en el tiempo con la avería de los extractores de aire en algunas habitaciones de la planta indican que la transmisión aérea desempeñó un papel fundamental en el desarrollo del brote (AU)

Background and objectives Despite the increasing evidence supporting the importance of airborne transmission in SARS-CoV-2 infection, it has not been considered relevant in the vast majority of reported nosocomial outbreaks of COVID-19. The aim of this study is to describe a nosocomial outbreak of SARS-CoV-2 infection whose features suggest that aerosol transmission had an important role. Methods This is a descriptive analysis of a nosocomial outbreak of SARS-CoV-2 infection in an internal medicine ward that occurred in December 2020. All cases were confirmed by a positive PCR test for SARS-CoV-2. Results From December 5 to December 17, 21 patients and 44 healthcare workers developed a nosocomial SARS-CoV-2 infection. Fifty-one of the 65 cases (78.5%) were diagnosed between December 6 and 9. The attack rate in patients was 80.8%. Among workers, the attack rate was higher in those who had worked at least one full working day in the ward (56.3%) than in those who had occasionally been in the ward (25.8%, p=0.005). Three days before the first positive case was detected, 2extractor fans were found to be defective, affecting the ventilation of 3rooms. Sixteen cases were asymptomatic, 48 cases had non-severe symptoms, and 2 cases required admission to the intensive care unit. All patients eventually recovered. Conclusion The high attack rate, the explosive nature of the outbreak, and the coincidence in time with the breakdown in air extractors in some rooms of the ward suggest that airborne transmission played a key role in the development of the outbreak (AU)

Nosocomial outbreak of COVID-19 in an internal medicine ward: Probable airborne transmission.

BACKGROUND AND OBJECTIVES: Despite the increasing evidence supporting the importance of airborne transmission in SARS-CoV-2 infection, it has not been considered relevant in the vast majority of reported nosocomial outbreaks of COVID-19. The aim of this study is to describe a nosocomial outbreak of SARS-CoV-2 infection whose features suggest that aerosol transmission had an important role. METHODS: This is a descriptive analysis of a nosocomial outbreak of SARS-CoV-2 infection in an internal medicine ward that occurred in December 2020. All cases were confirmed by a positive PCR test for SARS-CoV-2. RESULTS: From December 5 to December 17, 21 patients and 44 healthcare workers (HCWs) developed a nosocomial SARS-CoV-2 infection. Fifty-one of the 65 cases (78.5%) were diagnosed between December 6 and 9. The attack rate in patients was 80.8%. Among HCWs, the attack rate was higher in those who had worked at least one full working day in the ward (56.3%) than in those who had occasionally been in the ward (25.8%; p = 0.005). Three days before the first positive case was detected, two extractor fans were found to be defective, affecting the ventilation of three rooms. Sixteen cases were asymptomatic, 48 cases had non-severe symptoms, and 2 cases required admission to the intensive care unit. All patients eventually recovered. CONCLUSION: The high attack rate, the explosive nature of the outbreak, and the coincidence in time with the breakdown in air extractors in some rooms of the ward suggest that airborne transmission played a key role in the development of the outbreak.

[Nosocomial outbreak of COVID-19 in an internal medicine ward: Probable airborne transmission]. / Brote nosocomial de COVID-19 en una planta de medicina interna: probable transmisión aérea.

Background and objectives: Despite the increasing evidence supporting the importance of airborne transmission in SARS-CoV-2 infection, it has not been considered relevant in the vast majority of reported nosocomial outbreaks of COVID-19. The aim of this study is to describe a nosocomial outbreak of SARS-CoV-2 infection whose features suggest that aerosol transmission had an important role. Methods: This is a descriptive analysis of a nosocomial outbreak of SARS-CoV-2 infection in an internal medicine ward that occurred in December 2020. All cases were confirmed by a positive PCR test for SARS-CoV-2. Results: From December 5 to December 17, 21 patients and 44 healthcare workers developed a nosocomial SARS-CoV-2 infection. Fifty-one of the 65 cases (78.5%) were diagnosed between December 6 and 9. The attack rate in patients was 80.8%. Among workers, the attack rate was higher in those who had worked at least one full working day in the ward (56.3%) than in those who had occasionally been in the ward (25.8%, p = 0.005). Three days before the first positive case was detected, 2 extractor fans were found to be defective, affecting the ventilation of 3 rooms. Sixteen cases were asymptomatic, 48 cases had non-severe symptoms, and 2 cases required admission to the intensive care unit. All patients eventually recovered. Conclusion: The high attack rate, the explosive nature of the outbreak, and the coincidence in time with the breakdown in air extractors in some rooms of the ward suggest that airborne transmission played a key role in the development of the outbreak.

Impact of a training program on the surveillance of Clostridioides difficile infection.

A high degree of vigilance and appropriate diagnostic methods are required to detect Clostridioides difficile infection (CDI). We studied the effectiveness of a multimodal training program for improving CDI surveillance and prevention. Between 2011 and 2016, this program was made available to healthcare staff of acute care hospitals in Catalonia. The program included an online course, two face-to-face workshops and dissemination of recommendations on prevention and diagnosis. Adherence to the recommendations was evaluated through surveys administered to the infection control teams at the 38 participating hospitals. The incidence of CDI increased from 2.20 cases/10 000 patient-days in 2011 to 3.41 in 2016 (P < 0.001). The number of hospitals that applied an optimal diagnostic algorithm rose from 32.0% to 71.1% (P = 0.002). Hospitals that applied an optimal diagnostic algorithm reported a higher overall incidence of CDI (3.62 vs. 1.92, P < 0.001), and hospitals that were more active in searching for cases reported higher rates of hospital-acquired CDI (1.76 vs. 0.84, P < 0.001). The results suggest that the application of a multimodal training strategy was associated with a significant rise in the reporting of CDI, as well as with an increase in the application of the optimal diagnostic algorithm.

Vegetarianism and breast, colorectal and prostate cancer risk: an overview and meta-analysis of cohort studies.

BACKGROUND: Vegetarian diets may be associated with certain benefits toward human health, although current evidence is scarce and contrasting. In the present study, a systematic review and meta-analysis of prospective cohort studies was performed with respect to the association between vegetarian diets and breast, colorectal and prostate cancer risk. METHODS: Studies were systematically searched in Pubmed and EMBASE electronic databases. Eligible studies had a prospective design and compared vegetarian, semi- and pesco-vegetarian diets with a non-vegetarian diet. Random-effects models were applied to calculate relative risks (RRs) of cancer between diets. Statistical heterogeneity and publication bias were explored. RESULTS: A total of nine studies were included in the meta-analysis. Studies were conducted on six cohorts accounting for 686 629 individuals, and 3441, 4062 and 1935 cases of breast, colorectal and prostate cancer, respectively. None of the analyses showed a significant association of vegetarian diet and a lower risk of either breast, colorectal, and prostate cancer compared to a non-vegetarian diet. By contrast, a lower risk of colorectal cancer was associated with a semi-vegetarian diet (RR = 0.86, 95% confidence interval = 0.79-0.94; I2 = 0%, Pheterogeneity = 0.82) and a pesco-vegetarian diet (RR = 0.67, 95% confidence interval = 0.53, 0.83; I2 = 0%, Pheterogeneity = 0.46) compared to a non-vegetarian diet. The subgroup analysis by cancer localisation showed no differences in summary risk estimates between colon and rectal cancer. CONCLUSIONS: A summary of the existing evidence from cohort studies on vegetarian diets showed that complete exclusion of any source of protein from the diet is not associated with further benefits for human health.

Dietary patterns and risk of colorectal adenoma: a systematic review and meta-analysis of observational studies.

BACKGROUND: Current evidence suggests that dietary patterns may play an important role in colorectal cancer risk. The present study aimed to perform a systematic review and meta-analysis of observational studies exploring the association between dietary patterns and colorectal adenomas (a precancerous condition). METHODS: Pubmed and EMBASE electronic databases were systematically searched to retrieve eligible studies. Only studies exploring the risk or association with colorectal adenomas for the highest versus lowest category of exposure to a posteriori dietary patterns were included in the quantitative analysis. Random-effects models were applied to calculate relative risks (RRs) of colorectal adenomas for high adherence to healthy or unhealthy dietary patterns. Statistical heterogeneity and publication bias were explored. RESULTS: Twelve studies were reviewed. Three studies explored a priori dietary patterns using scores identifying adherence to the Mediterranean, Paleolithic and Dietary Approaches to Stop Hypertension (DASH) diet and reported an association with decreased colorectal adenoma risk. Two studies tested the association with colorectal adenomas between a posteriori dietary patterns showing lower odds of disease related to plant-based compared to meat-based dietary patterns. Seven studies identified 23 a posteriori dietary patterns and the analysis revealed that higher adherence to healthy and unhealthy dietary patterns was significantly associated risk of colorectal adenomas (RR = 0.81, 95% confidence interval = 0.71, 0.94 and RR = 1.24, 95% confidence interval = 1.13, 1.35, respectively) with no evidence of heterogeneity or publication bias. CONCLUSIONS: The results of this systematic review and meta-analysis indicate that dietary patterns may be associated with the risk of colorectal adenomas.

Prevalence of antibodies to Rickettsia conorii in human beings and dogs from Catalonia: a 20-year perspective.

The incidence of Mediterranean spotted fever (MSF) in Catalonia (Spain) has decreased in the last two decades. The prevalence of antibodies to Rickettsia conorii in human beings and dogs in the region of Vallès Occidental (Catalonia) was assessed by indirect immunofluorescence, and the results compared with those obtained in a similar study from 1987. Nineteen (5·0%) out of 383 human serum samples had antibodies to R. conorii. This seroprevalence was significantly lower (11·5%) (P = 0·003) than that recorded in the 1987 survey. Forty-two out (42·0%) of 100 canine serum samples had antibodies to R. conorii. A high proportion of the studied dogs (91·0%) were receiving anti-tick treatment, mainly with permethrin-imidacloprid spot-on (Advantix, Bayer, Germany). The current canine seroprevalence was not significantly different from that recorded in the 1987 survey (36.9%). In conclusion, this study shows a significant decrease in the prevalence of antibodies to R. conorii in the human population of Catalonia in the last 20 years, which corresponds with a decrease in the number of cases of MSF. We suggest that the widespread use of anti-tick treatment in dogs could limit the introduction of ticks to humans due to a reduction of infestation duration in dogs, thus contributing to the decrease in MSF incidence.

Unveiling iodine-based electrolytes chemistry in aqueous dye-sensitized solar cells.

Aqueous dye-sensitized solar cells (DSSCs) have recently emerged as promising systems, which can combine low cost and environmental compatibility with appreciable efficiency, long-term durability and enhanced safety. In the present study, we thoroughly investigate the chemistry behind the iodide/triiodide-based redox mediator, which presents - in a completely aqueous environment - several differences when compared to the behavior observed in the conventionally used organic solvents. The speciation of ions, the effect of the concentration of the redox mediator and the type of counter-ion are characterized from the electrochemical, spectroscopic, photovoltaic and analytical viewpoints. Furthermore, we demonstrate that aqueous DSSCs, often assumed as unstable, hold the potential to assure unparalleled stability after five months of aging without any addition of stabilizers or gelling agents, thus envisaging the construction of eco-friendly photovoltaic devices free of expensive, flammable and toxic solvents.

Telemedicine Home Program in Patients with Cystic Fibrosis: Results after 10 Years.

OBJECTIVES: We studied the effect of Telehomecare (THC) in a group of cystic fibrosis (CF) patients. MATERIALS AND METHODS: Forced Expiratory Volume in the first second (FEV1) was monitored at home, with the aim of an early recognition of the relapses of pulmonary infections. FEV1 was monitored for 4.5 years, using THC as a tool, in addition to the standard therapeutic protocol. 16 CF patients were followed by doctors experts in the treatment of CF, over a period of 4.5 years. We compared a control group among patients seen in the past for an identical period, matching for number, age, sex, respiratory function, bacterial colonization, O2 dependency, and complications. 16 CF patients with similar characteristics of age, degree of pulmonary involvement, bacterial colonization and O2 dependency. We calculated the annual mean values of FEV1 in both groups. RESULTS: Spirometry data showed a significant improvement in annual Fev1 mean values for the THC patients as compared to the control group. DISCUSSION: The data are encouraging for a possible role of Telemedicine as a tool for domestic assistance of patients affected by chronic diseases, such as CF. However, reliable data on the long-term effectiveness of the use of THC in the treatment of CF patients is still lacking. The time has come to obtain reliable data through a multicenter collaboration study, also in order to standardize the international Telemedicine protocols.

Impact of a multimodal intervention to reduce bloodstream infections related to vascular catheters in non-ICU wards: a multicentre study.

To determine the impact of a multimodal intervention designed to reduce the incidence of catheter-related bloodstream infections (CRBSIs) outside the ICU, we conducted a prospective, quasi-experimental, before-after intervention study in 11 hospitals participating in the VINCat programme in Catalonia, Spain. The intervention consists of: (i) an evidence-based bundle of practices relating to catheter insertion and maintenance; (ii) a training programme for healthcare workers; (iii) four point-prevalence surveys to track the status of the catheters; and (iv) feedback reports to the staff involved. The study included both central (CVC) and peripheral venous catheters (PVCs). Rates of CRBSI per 1000 patient-days were prospectively measured in 2009 (pre-intervention period) and 2010 (post-intervention period). The analysis included 1 191 843 patient-days in 2009 and 1 173 672 patient-days in 2010. The overall incidence of CRBSI decreased from 0.19 to 0.15 (p 0.04) and the incidence of CRBSI associated with a CVC decreased from 0.14 to 0.10 (p 0.004) after the intervention. The incidence in PVCs remained unchanged. There was a statistically significant improvement in the adequate maintenance of both CVCs and PVCs. Among the CRBSIs originating in PVCs, 61.8% appeared more than 72 h every insertion. There was a lower infection rate in the hospitals with a higher adherence to the recommendation to replace PVCs after 72 h. Our findings suggest that the implementation of intervention programmes similar to ours could have a major impact on patient safety by reducing the incidence of CRBSIs, and that routine replacement of PVCs might additionally prevent a significant number of bloodstream infections.

Remote telematic control in cystic fibrosis.

INTRODUCTION: In this study we describe and discuss the way we daily act in remote telematic tracking of CF outpatients, a procedure which has been improved through our daily experience in telehomecare. MATERIALS AND METHODS: Currently, there are almost 30 patients involved in our telehomecare project. We describe and discuss intervention parameters and the way we manage a register of performances in spreadsheet format. We also describe the training program for the patients and their and the procedures through which we maintain contacts with patients and Vivisol assistance and the periodical satisfaction surveys. RESULTS: (from 15 of february 2010 to 24 of may 2011). Total transmissions 882, Spirometry 1317, SaO2 291, Compliance (transmissions/patient days) 8,91%, Hospital controls 19, Total contacts 722, Phone calls 494. DISCUSSION: We analyze the 2010 - 2011 data. We discuss the compliance of patients toward Telehomecare, the efficacy of cell phone in establishing contact with patients and the relevancy of symptoms' rescue in diagnosing the pulmonary relapse episodes. We discuss medico-legal aspects of telemedicine activity, in the light of standards and legislation, including issues related to the processing of privacy and security data. We discuss the professional team needs and requirements, dedicated to the activities of telemedicine and procedures related to clinical risk management. We conclude by underlying how telemedicine represents a promising new tool for patients and health professionals, and that under certain conditions it can improve the assistance, working conditions and also to reduce costs. However, its usage has to be followed by precise studies about its efficacy, and also by paying particular attention to the partly new issues that derive from it.

Bloodstream infections in adults: importance of healthcare-associated infections.

OBJECTIVE: The objective of this study was to evaluate the characteristics of bloodstream infections occurring among outpatients having recent contact with the health care system compared to hospital and community-acquired infections. METHODS: Prospective observational cohort study of adult patients with bloodstream infections at three teaching hospitals. Bloodstream infection was defined as hospital-acquired if the first positive blood culture was performed more than 48 h after admission. Other bloodstream infections were classified as healthcare-associated or community-acquired. RESULTS: A total of 1157 episodes of bloodstream infections were studied; 581 (50.2%) were community-acquired, 295 (25.5%) were hospital-acquired, and 281 (24.3%) were health care-associated. Of the 281 health care-associated bloodstream infections, 68 (24%) occurred in patients residing in a nursing home, 104 (37%) in patients receiving intravenous therapy, health care at home, chemotherapy or attending dialysis, and 169 (60%) in patients hospitalized during the 90 days before their bloodstream infection (some patients belonged to more than one risk category). The highest prevalence rate of MRSA infections occurred in healthcare-associated infections (5%) (p<0.001). A significantly higher mortality rate was seen in the group with healthcare-associated infections (27.5%) than in community-acquired infections (10.4%) (p<0.001). CONCLUSIONS: Our results confirm that healthcare-associated bloodstream infections show important differences from community-acquired bloodstream infections and suggest that empirical antibiotic therapy should be similar to hospital-acquired bloodstream infections, taking into account the epidemiologic characteristics of each region.

Efficacy and tolerability of prolonged linezolid therapy in the treatment of orthopedic implant infections.

The aim of the study presented here was to assess the efficacy and tolerability of linezolid in the treatment of orthopedic implant infections (OII). Eighty-five patients with an OII treated with linezolid were prospectively followed up for a minimum of 12 months from the end of antibiotic therapy. Outcome was evaluated in relation to the duration and type of symptoms (acute or chronic) and the retention or removal of the implant. For acute and chronic infections, the respective success rates were 100 and 92.3% when the implant was removed and 72.2 and 42.8% when it was not. The median length of linezolid treatment in acute and chronic infections was 47 and 60 days, respectively. Thrombocytopenia was observed in four (4.7%) patients and anemia in five (5.8%). The results suggest oral linezolid is an effective and well-tolerated alternative for treating OII.

[Fecal incontinence. Personal experience in direct sphincteric repair]. / Incontinenza fecale. Nostra esprienza nella riparazione sfinterica diretta.

BACKGROUND: Fecal incontinence is a disabling condition causing social isolation, whose real incidence is difficult to be exactly valued because patients are often reluctant to speak about it, even with their physician, or because they don't trust on surgical procedure. Aim of this study is report our experience in sphincteric reconstruction by direct sphincteric repair in patients suffering from post-traumatic fecal incontinence. METHODS: Seven patients suffering from fecal incontinence due to traumatic lesions of anal sphincterial apparatus were surgically treated between 1981-2000; in the first patient cause was an injury due to impaling, in the second a previous obstetrical lesion and in the last five a previous fistulectomy. Direct sphincteric reconstruction after finding and isolation of two retracted terminals of sectioned sphincter was performed in all the patients. Sphincteric reconstruction has been always accompanied by total parenteral nutrition for about two weeks during the postoperative period. A protective colostomy was never performed. RESULTS: In five cases the results were excellent: patients had continence total recovery and postoperative manometry recorded basal and voluntary contraction pressures normalisation. In the two remaining cases there was only a modest improvement because of concomitant pudendal neuropathy. No operative wound infection was observed. CONCLUSIONS: We hope that more attention is paid to fecal incontinence either regarding instrumental semeiotics or medical or surgical therapy. In particular, direct sphincteroplasty can restore a satisfactory continence in a strong number of patients with anal sphincterial apparatus single traumatic lesions without pudendal neuropathy, relieving them from a heavily disabling condition.

Use of Erbium:YAG laser in the treatment of palpebral xanthelasmas.

OBJECTIVE: In light of the research and the use of lasers in the therapy of xanthelasmas, the authors report their experience in the treatment of this pathology with Erbium:YAG laser. MATERIALS AND METHODS: In 30 patients, all female, 70 xanthelasmas were treated with Erbium:YAG laser, 65 (93%) of which were on the upper eyelid and 5 (7%) on the lower eyelid, varying from 1 x 1.5 mm to 11 X 20 mm in size. Spots with a diameter of 1.6 mm, energy of 300 mJ, frequency of 1-5 Hz and in a number varying were used in relation to the extent of the pathology. RESULTS: In all cases, the appearance and functional results were good, without leaving scars and/or dyschromia. CONCLUSIONS: Erbium:YAG laser, in the treatment of xanthelasmas, is a parasurgical method that is simple to perform and because of the successful aesthetic and functional results, is a valid alternative to the more traditional treatment methods.

[Our experience in the transanal excision of tubulovillous adenomas of the rectum]. / Nostra esperienza in tema di escissione per via transanale degli adenomi tubulo-villosi del retto.

BACKGROUND: Personal experience on transanal excision of rectal adenomas without affecting sphincteric function is reported. METHODS: From 1985 to 1997, 27 patients suffering from rectal adenomatous polyps underwent surgery; the sites of lesions were within 3 to 10 cm from anal orifice in the whole series; the age of patients ranged from 30 to 81 years. Two different procedures were employed: the Parks' technique and the electroresection by traction flap technique according to Faivre. RESULTS: Any postsurgical complication such as hemorrhage, stenosis or incontinentia occurred; surgical mortality was absent. Histological examination disclosed severe dysplasia as well as in situ carcinoma in 6 patients (22.2%) and malignant polyps in 9 patients (33.3%). Only in a case a palliative excision was performed since the poor general conditions of this patient did not permit a more extended treatment; a local relapse of the tumour associated with liver metastases led the patient to death 22 months after surgery. Three patients were lost to follow-up and 2 patients died because of other causes, 6 and 8 years after surgical excision, respectively. CONCLUSIONS: The conclusions are is drawn that either Park's and Faivre's procedures are useful and safe for the surgical treatment of rectal villous polyps extended up to 8-12 cm from anal orifice, in spite of the presence of malignant foci within their mass. These surgical procedures are simple and relatively poor traumatic; for this reason they are more suitable than other transabdominal or abdomino-perineal approaches for older patients and other at risk-patients. It is underlined that the treated patients require a long-term follow-up aimed at the early diagnosis of possible relapses of adenomatosis.

[Our experience in internal medioposterior sphincterotomy with anoplasty]. / Nostra esperienza in tema di sfinterotomia interna mediana posteriore con anoplastica.

BACKGROUND: The technique of the posterior medial internal sphincterotomy according to Arnous is described and advice from personal experience reported. METHODS: From 1981 to 1995 posterior medial internal sphincterotomy with anoplasty was performed in 270 patients (132 males and 138 females) affected with chronic anal fissure, alone (112 cases) or associated with hemorrhoids (80 cases); moreover, the Arnous's operation was performed as well for hemorrhoids with posterior subsidiary packet and internal sphincter hypertonia (52 cases), relapsed hemorrhoids with postoperative anal stenosis (24 cases) and postoperative anal stenosis with painful fissure and residual internal sphincter hypertonia (2 cases). RESULTS: The results have been excellent; the average stay in hospital has been 7 days and the complete recovery occurred after 4-6 weeks without early or late complications. CONCLUSIONS: The importance of anorectal manometry for the preoperative valuation of the sphincteric hypertonia is emphasized: in this manner it is possible to modulate the sphincterotomy avoiding too economic sphincteric sections with next residue hypertonia or, in the contrary, too plentiful sphincteric section with problems of continence. Finally, the internal lateral-left sphincterotomy is mentioned, which is efficacious in the treatment of acute anal fissure. However, the proctological surgeon, on the basis of his experience, will propose the most convenient technique.

Ultrasound biomicroscopy in the clinical evaluation of ab externo holmium:YAG laser sclerostomies.

High-frequency ultrasound biomicroscopy (UBM) has extensive powers of resolution. This makes it possible to explore and study some areas of the anterior segment with a clarity close to that of histologic preparations. High-frequency UBM was used in the clinical evaluation of 10 glaucomatous eyes subjected to ab externo holmium:yttrium-aluminum-garnet (Ho:YAG) laser sclerostomy. The anatomic characteristics of the fistular paths were viewed and compared with echographic images. The authors demonstrated that in the 5 cases where the filtering bleb, fistular path, and internal ostium were present, there was a reduction of intraocular pressure. UBM is a high-definition diagnostic instrument in the follow-up of fistular paths and filtering blebs after Ho:YAG laser sclerostomy, making it possible to reoperate at an early stage before the onset of clinical manifestations.

Epidemiology of an unusually prolonged outbreak of typhoid fever in Terrassa, Spain.

An unusually prolonged outbreak of typhoid fever, from 1988 to 1994, in Terrassa (Barcelona, Spain), was caused by a casual food handler who was a carrier. The pattern of this outbreak suggested intermittent low-level exposure to Salmonella typhi. We found 70 patients with S. typhi infections, 52 of whom were available for study. Medical records were reviewed and patients were interviewed with use of a standard questionnaire. Phage typing and pulsed-field gel electrophoresis (PFGE) for strain subtyping were used to confirm the epidemiological data. The 27 outbreak strains shared the same phage type and the same PFGE pattern. Four sporadic strains shared the same phage type as the outbreak strain. PFGE was found to be useful for differentiating strains for epidemiological purposes.