Acute fascioliasis--clinical and epidemiological features of four patients in Chile.

Because of its infrequent and protean presentation and the lack of clinical data, the management of acute infections with the foodborne trematode Fasciola hepatica is challenging. We report four serologically confirmed cases that illustrate our experience with this parasitic infection in Chile. All patients were adults presenting with upper abdominal pain. Other symptoms included fever, nausea/vomiting, and cutaneous manifestations. In all cases, marked eosinophilia was present. All patients lived in an urban environment, and three reported the consumption of raw watercress. Computed tomography (CT) scans showed hypodense hepatic lesions, whereas ultrasonography findings were unremarkable. One patient suffered portal vein thrombosis, which might be a rare complication of acute fascioliasis. All patients were successfully treated with triclabendazole. Our case series demonstrates that patients with acute fascioliasis typically present with a combination of upper abdominal pain, marked eosinophilia, and hypodense hepatic lesions on CT imaging. Diagnosis should be confirmed by serological investigation. A history of recent consumption of raw watercress is an important finding, but in some patients the source of infection remains obscure.

Immunohistochemically proven cytomegalovirus end-organ disease in solid organ transplant patients: clinical features and usefulness of conventional diagnostic tests.

We studied the main clinical features, outcome, and laboratory parameters in a group of solid organ transplant (SOT) patients with immunohistochemically proven cytomegalovirus (CMV) disease. Confirmed CMV cases were obtained through databases. Demographics, clinical data, transplantation type, immunosuppressive regimens, donor and recipient CMV serostatus, therapy, outcome and laboratory results, pp65 antigenemia, and qualitative polymerase chain reaction (PCR) for CMV were analyzed. From 1995 to 2004, 31 cases with complete medical records were identified. Disease appeared between 24 and 2538 days after transplantation but most cases presented in the first 100 days. Gastrointestinal CMV disease was the most frequent form (71%), while thrombocytopenia was present in 50% of cases, and leukopenia was less common (35.5%). CMV pp65 antigenemia was positive in 58% of patients, but its sensitivity increased to 71% if performed during the first 6 months. A qualitative CMV PCR technique gave similar results during this period (71.4%). Most patients were treated with intravenous ganciclovir (n=25; 80.6%). In 4 cases (19.4%), use of foscarnet alone or a sequential regimen with ganciclovir-foscarnet was deemed necessary. Surgical procedures were necessary in 5 patients (16%). The death rate reached 13%. CMV end-organ disease can be a life-threatening infection in SOT patients. Gastrointestinal disease was the most frequent end-organ disease. CMV antigen detection is best suited for the early period after transplantation.

Oral ulcers produced by mycophenolate mofetil in two liver transplant patients.

Oral ulcers are a frequent problem in transplant medicine. It is important to consider infectious etiologies, exacerbated by the immunosuppressive treatment, but other etiologies are also possible, like adverse drug reactions. Mycophenolate mofetil (MMF) is an immunosuppressive medication that has been used in combination with calcineurin inhibitors and steroids. Reports of renal transplant patients with oral ulcers related to MMF have appeared lately and herein we have described 2 cases in liver transplant patients. Their oral ulcers resolved quickly after suspension of the medication. Our 2 cases in liver transplant patients represented a unique setting for this type of complication.

Espondilodiscitis. Análisis de una serie de 25 casos / Spondylodiscitis. Analysis of 25 cases

BACKGROUND: Spondylodiscitis is a rare but prolonged inflammation of two adjacent vertebral bodies and the disk in between. AIM: To report the clinical features of a series of patients with spondylodiscitis. MATERIAL AND METHODS: A retrospective analysis of medical records of patients with spondylitis, identified between 1989 and 2002. RESULTS: A total of 25 cases were identified, 15 female, aged 49.8 years as a mean. Their mean evolution before admission was 4.3 months. Main complaints were back or radicular pain. Mild anemia was present in most patients. Mean erythrocyte sedimentation rate and C reactive protein values were 66 mm/h and 60 mg/L, respectively. Forty four percent of patients had neurological complications. Vertebral computed tomography and scintigraphic studies were done in 72 per cent of patients, but magnetic resonance imaging was done only in 4 (16 per cent). In 18 patients, a tissue sample for pathological and microbiological analysis, was obtained by imaging guiding or surgically. Tuberculosis, diagnosed on pathology, was the leading cause of spondylitis in nine cases (36 per cent), followed by Staphylococcus aureus infection in five (20 per cent). Other agents found were E coli and group D Streptococcus (one each). Age, symptoms, evolution time and different laboratory parameters did not differ between patients with tuberculosis and patients with other causes. A microbiological cause was not established in 36 per cent of cases. Most patients evolved satisfactorily and recovered from neurological complications (88 per cent). One patient with tuberculosis did not improve after prolonged treatment and 2 patients infected with S aureus died (8 per cent). CONCLUSIONS: Spondylodiscitis is associated to a diversity of microbial agents and in most cases has a favorable prognosis.

[Phage typing of Salmonella enteritidis isolated from clinical, food, and poultry samples in Chile]. / Tipificación fágica de aislados de Salmonella enteritidis de muestras clínicas, alimentarias y avícolas en Chile.

Since 1994 an extensive epidemic of infections with Salmonella enteritidis (S. enteritidis) has affected Chile. In order to understand the diversity of infective sources, the possible origin of the epidemic, and the epidemiological relationships between clinical, food, and poultry isolates, we carried out phage typing of three groups of samples: 1) 310 S. enteritidis clinical samples collected between 1975 and 1996, 2) 47 food isolates obtained during S. enteritidis outbreaks, and 3) 27 strains isolated in surveillance studies of poultry-raising establishments. With the clinical samples, a total of 13 phage types were identified, 2 isolates could not be typed, and 1 was considered atypical. The phage types that were identified most frequently were 1 (56.8%) and 4 (31.3%), trailed by type 8 (4.8%) and type 28 (1.9%). Over time and in different regions of the country there were major changes in the distribution of the phage types. In the first years of collection the only phage types registered were 8 and 28, which disappeared around 1980 and then began reappearing sporadically in 1996. With the gradual S. enteritidis expansion that started in 1988, in the central and southern areas of the country phage type 4 began to appear; that type had not been found before in Chile. In 1991 in the northern area of the country phage type 1 began to predominate; it was another type that had not been reported before in Chile. In the food isolates the only phage types identified were 1 and 4, which were also the most common in the poultry isolates. Phage typing of S. enteritidis has proved to be useful in guiding the epidemiological analysis of the infections caused by this pathogen.

[Detection of pyrogenic exotoxin SpeA, SpeB and SpeC genes in Chilean streptococci isolates and their association with clinical manifestations]. / Detección de los genes de las exotoxinas pirogénicas SpeA, SpeB y SpeC en cepas chilenas de Streptococcus pyogenes y su asociación con la clínica.

BACKGROUND: The virulence of Streptococcus pyogenes is determined by a variety of structural molecules, toxins and complex enzymes. Pyrogenic exotoxins cause fever, erythematous reactions, cytotoxic and immunological effects. AIM: To assess the frequency of speA, SpeB and SpeC genes in Chilean Streptococcus pyogenes strains and their association with the invasiveness of infections. MATERIAL AND METHODS: The genes for pyrogenic exotoxins SpeA, SpeB and SpeC were determined by polymerase chain reactions in 114 strains of group A Streptococcus pyogenes isolated from Chilean patients with invasive or non invasive infections. RESULTS: The gene for SpeA was present in 30.7% of isolates, the gene for SpeB was present in 69.3% and the gen for SpeC in 44.7% of isolates. The gene for SpeA was present in 20 of 33 invasive infections and in 15 of 81 non invasive infections (p < 0.0001). On the contrary, the gene for SpeC was present in 11 of 33 invasive infections and in 41 of 81 non invasive infections (p < 0.05). The frequency of speB was similar in invasive and non invasive infections. CONCLUSIONS: There is a clear relationship between the presence of SpeA genes and the severity of infections caused by Streptococcus pyogenes.

[Detection of Salmonella enteritidis in samples of poultry products for human consumption in the Chilean metropolitan area]. / Detección de Salmonella enteritidis en muestras de productos avícolas de consumo humano en la Región Metropolitana.

BACKGROUND: Salmonella enteritidis (SE) is a frequent cause of diarrhea, and is transmitted mainly by SE contaminated eggs or poultry meat. The frequency of SE contaminated eggs or chicken meat and the risk for acquiring this pathogen is unknown in Chile. AIM: To measure SE contamination in eggs poultry meat and entrails offered in retail markets in the Metropolitan Area during two consecutive years (1998-1999). MATERIAL AND METHODS: Samples were placed in sterile bags and transported to the laboratory before 4 hours at 4 degrees C. Microbiologic detection was done using a standard procedure and an immunodetection assay. RESULTS: SE was found in one of 1081 egg samples (0.09%). The contaminated sample was offered in a supermarket under their own commercial name. Six percent of 1154 poultry meat samples were contaminated by SE and 2.3% by other Salmonella serotypes. Entrails had even higher rates with 10.2% of 370 samples harboring SE and 2.7% other serotypes. Total Salmonella sp. isolates and SE isolates declined during 1999. Nine SE phagotypes were identified, predominating types 4 and 7. CONCLUSIONS: Eggs and other avian products are contaminated by different SE phagotypes and other Salmonella serotypes, implicating a risk for the consumers (Rev Méd Chile 2000; 128: 1075-83).

Clonal diversity of Chilean isolates of enterohemorrhagic Escherichia coli from patients with hemolytic-uremic syndrome, asymptomatic subjects, animal reservoirs, and food products.

To determine clonal relationship among Chilean enterohemorrhagic Escherichia coli (EHEC) strains from different sources (clinical infections, animal reservoirs, and food), 54 EHEC isolates (44 of E. coli O157, 5 of E. coli O111, and 5 of E. coli O26) were characterized for virulence genes by colony blot hybridization and by pulsed-field gel electrophoresis (PFGE). By colony blotting, 12 different genotypes were identified among the 44 E. coli O157 isolates analyzed, of which the genetic profile stx1+ stx2+ hly+ eae+ was the most prevalent. All human O157 strains that were associated with sporadic cases of hemolytic-uremic syndrome (HUS) carried both the stx1 and stx2 toxin-encoding genes and were eaeA positive. Only 9 of 13 isolates from human controls were stx1+ stx2+, and 8 carried the eaeA gene. Comparison of profiles obtained by PFGE of XbaI-digested genomic DNA showed a great diversity among the E. coli O157 isolates, with 37 different profiles among 39 isolates analyzed. Cluster analysis of PFGE profiles showed a wide distribution of clinical isolates obtained from HUS cases and asymptomatic individuals and a clonal relationship among O157 isolates obtained from HUS cases and pigs. Analysis of virulence genes showed that a correlation exists among strains with the genotype stx1+ stx2+ eae+ and pathogenic potential. A larger difference in the PFGE restriction patterns was observed among the EHEC strains of serogroups O26 and O111. These results indicate that several different EHEC clones circulate in Chile and suggest that pigs are an important animal reservoir for human infections by EHEC. Guidelines have been proposed for better practices in the slaughter of animals in Chile.

[Toxic shock syndrome by group A beta-hemolytic streptococcus. Study of clonal relationship between a case and its contacts]. / Síndrome de shock tóxico por Streptococcus beta-hemolítico grupo A. Estudio de la relación clonal entre un caso y sus contactos.

Group A Streptococcal infections have increased in severity and frequency worldwide. We report a female patient that was admitted by Group A Streptococcal lethal toxic shock syndrome due to pharyngitis as the primary focus and without cutaneous involvement. Streptococcus pyogenes was isolated from blood cultures and case definition fulfilled standard recommendations. Epidemiological studies among family members showed, that two children (aged 5 and 12 years) harbored the same strain in their pharynxes as confirmed by arbitrarily primed PCR (AP-PCR) using primers ERIC and Pn-1. Control strains were included in the analysis. None of three health care workers involved in intubation and laryngoscopic procedures with the patient carried S pyogenes. AP-PCR appears to be a useful and rapid procedure to demonstrate clonal relatedness among S pyogenes strains.

[Salmonella enteritidis, an emergent pathogen in Chile]. / Salmonella enteritidis, un patógeno emergente en Chile.

BACKGROUND: Salmonella enteritidis infections have increased worldwide in the last years. Isolation of this pathogen was remarkably rare in Chile until 1994, when the still ongoing outbreak emerged. AIM: To assess the main epidemiological characteristics of the Salmonella enteritidis epidemic in Chile. MATERIALS AND METHODS: Cases of clinical infections by Salmonella enteritidis were recorded from bacteriological and demographic notifications obtained at The National Reference Laboratory for Enterobacteria. Infection rates were calculated using the total Chilean population and the population of the different Health Services along the country. RESULTS: Until 1993, 13.67 Salmonella enteritidis strains per year were received at the Reference Laboratory. The figures increased to 478 and 432 in 1994 and 1995, respectively. National rates were 3.41 and 3.04 notifications/100,000 inhabitants in 1994 and 1995 respectively. Northern regions were the most affected and 90% of observed cases during 1994 came from Arica and Antofagasta. At the present time, 20% of cases are observed in Santiago, located in the mid-portion of the country. The outbreak has mainly affected children and young adults (70% of cases). Strains have been isolated from stool cultures, suggesting gastrointestinal infections as the main clinical presentation. More than 98% of strains are susceptible to chloramphenicol, ampicillin, tetracycline, sulfa-trimetroprim, cefotaxime or ciprofloxacin. CONCLUSIONS: The obtained data clearly indicate the existence of an epidemic outbreak of Salmonella enteritidis infections, with a geographic progression from North to South.

[E-test to study small inhibitor concentrations, bacterial diversity and to identify presumptively beta-lactamases in strains of Pseudomonas aeruginosa and Acinetobacter baumannii associated with +nosocomial infections]. / E-test para determinar concentraciones inhibitorias mínimas, estimar la diversidad bacteriana e identificar presuntivamente beta-lactamasas en cepas-de Pseudomonas aeruginosa y Acinetobacter baumannii asociadas a infecciones intrahospitalarias.

BACKGROUND: Pseudomonas aeruginosa and Acinetobacter baumanii are two important nosocomial agents that require permanent testing of their antimicrobial susceptibility. AIM: To use E-test to determine minimal inhibitory concentrations, estimate bacterial diversity and presumably identify B-lactamases of strains of Pseudomonas aeruginosa and Acinetobacter baumanii isolated from nosocomial infections. MATERIALS AND METHODS: Sixty eight strains of Pseudomonas aeruginosa and Acinetobacter baumanii isolated in a teaching hospital were analyzed with E-test strips to determine their minimal inhibitory concentrations for different antimicrobials. RESULTS: More than 75% of Acinetobacter baumanii were resistant to Piperacillin, Cefpirome, Cefepime, Gentamicin or Amikacin, 40% of strains were resistant to Ceftazidime, 27 and 53% of isolates had a decreased susceptibility to Meropenem and Piperacillin-tazobactam respectively. Twenty eight to 54% of Pseudomonas aeruginosa strains were resistant to Cefepime, Cefpirome, Ciprofloxacin and Gentamicin. Eighteen and 10% of strains were resistant to Meropenem and Imipenem respectively. Less than 10% of strains were resistant to Amikacin, Azireonam, Piperacillin-tazobactam or Ceftazidime. Most of beta-lactam resistance of Pseudomonas aeruginosa was associated to decreased susceptibility or resistance to Cefpirome, Cefepime or to Meropenem-Imipenem and did not match clearly with known beta-lactamase profiles. CONCLUSIONS: The knowledge of susceptibility of these bacteria responsible for nosocomial infections, will help to plan the appropriate use of antimicrobials.

Antibiotic-resistant Salmonella typhi from two outbreaks: few ribotypes and IS200 types harbor Inc HI1 plasmids.

To investigate factors that could be involved in the emergence of antibiotic resistant S. typhi, we characterized R plasmids and antibiotic resistant S. typhi strains from two outbreaks of typhoid in Peru and Chile. Differences in the Inc HI1 plasmids of Peruvian and Chilean strains were identified by conjugation and incompatibility studies and plasmid DNA characterization. Antibiotic-resistant S. typhi harboring Inc HI1 plasmids belonged to a reduced number of Pst1 and Cla1 ribotypes and IS200 types, in contrast to the high genetic diversity found among epidemic antibiotic-susceptible S. typhi. The low diversity of antibiotic-resistant S. typhi suggests that they may express properties that are related to both their ability to harbor Inc HI1 R plasmids and to disseminate.

[Dysenteric syndrome, acute renal failure and lethal septic shock associated to Salmonella enteritidis infection. Report of 3 cases]. / Sindrome disentérico, insuficiencia renal aguda y shock séptico letal asociados a infección por Salmonella enteritidis. Descripción de 3 casos.

Chile is being affected by an epidemic of S enteritidis infections since 1994, an increasingly important cause of morbidity worldwide. Although infections by this bacteria have been commonly associated to diarrhea and patients are usually not affected by complications, three patients required admission by dysentery (not reported in most published series), acute renal failure (ARF) and septic shock (SS), respectively, at the end of the summer season. S enteritidis was isolated from stool cultures in all three cases. A female patient (24) with disentery presented with fever and diarrhea associated with blood and mucus and localized abdominal pain in the lower right quadrant. Surgery was not required although laparotomy was considered in the first hours after admission. ARF was demonstrated in a male patient (50) by dehydration, increased creatinine plasma and BUN level (7, 19 and 103 mg/dl, respectively), and increased urinary Na level and anion gap (35 mEq/l). Hemodialysis was not required. A third patient was admitted by SS (male, 57, alcoholic), as demonstrated by hypotension despite fluid reposition, altered mental status, and multiorgan compromise. Haemodynamic monitorization showed a high cardiac index and a low systemic vascular resistance. CPK serum determinations indicated rhabdomyolysis. Patients recovered satisfactorily, except SS patient, who died.

Epidemic typhoid in Chile: analysis by molecular and conventional methods of Salmonella typhi strain diversity in epidemic (1977 and 1981) and nonepidemic (1990) years.

From 1977 to 1986, Chile experienced an important typhoid fever epidemic, despite statistics that indicated apparently improving levels of sanitation of drinking water and sewage disposal. The lack of antibiotic resistance among the Salmonella typhi strains isolated during this period, the mild clinical presentation of the disease, and the initially low level of efficacy of the S. typhi Ty21a vaccine in the population exposed to the epidemic suggested that this epidemic might have resulted from the dissemination of S. typhi strains with unique characteristics. To investigate this hypothesis, we used conventional methods (bacteriophage typing and biotyping) and molecular methods (restriction fragment length polymorphism analysis, ribotyping, IS200 typing, and PCR amplification of the fliC-d gene) to study a population of 149 S. typhi isolates during 1977, 1981, and 1990, the years that included periods with low (when the disease was endemic) and high (when the disease was epidemic) morbidities. Our results indicate that these S. typhi isolates in Chile represent a number of highly diverse variants of the clone of S. typhi with a worldwide distribution described by Selander et al. (R. K. Selander, P. Beltran, N.H. Smith, R. Helmuth, F.A. Rubin, D.J. Kopecko, K. Ferris, B.D. Tall, A. Cravioto, and J.M. Musser, Infect. Immun. 58:2262-2275, 1990). For example, we detected 26 PstI and 10 ClaI ribotypes among 47 and 16 S. typhi strains belonging to this clone, respectively. These results suggest that the Chilean epidemic was probably produced by multiple sources of infection because of deficient sanitary conditions. These findings illustrate the usefulness of molecular methods for characterizing the potential causes of the typhoid epidemics and the possible routes of transmission of S. typhi strains in typhoid epidemics.

Salmonella typhi iron uptake mutants are attenuated in mice.

Iron starvation interferes drastically with the multiplication and virulence of Salmonella typhi mutants defective in enterochelin synthesis or enterochelin transport. Growth of these mutants is inhibited in the presence of human sera and unsaturated transferrin and is restored by fully saturated transferrin. The mutants exhibit decreased ability to grow in HeLa cell monolayers and are attenuated in mice. These findings are consistent with the S. typhi enterochelin system playing a role in the pathogenesis of typhoid fever.

Demonstration of persistence of Salmonella typhimurium in an AIDS patient by molecular methods.

We document microbiological persistence of the same Salmonella typhimurium strain in an AIDS patient during 7 months of clinical observation despite prolonged quinolone therapy. Persistence was demonstrated by phage types that closely resembled one another, similar antibiotic resistance patterns, conserved restriction fragment length polymorphism of chromosomal DNA digested with different DNA restriction enzymes, identical ribotypes, and IS200 types in four characterized sequential isolates of S. typhimurium.

[Genetic, molecular, and immunologic aspects of Vibrio cholerae infection]. / Aspectos genéticos, moleculares e inmunológicos de la infección por Vibrio cholerae.

The deterioration of the economical and social conditions of the majority of the population in the Americas the last 20 years has generated several epidemics of enteric infections in the region, dramatically manifested by the current massive and widespread cholera outbreak. The absence of cholera from the continent for more than 100 years, the worsening environmental conditions, the biological peculiarities of Vibrio cholerae El Tor such as decreased virulence, which generates increased number of carriers, and its improved ability to thrive in the environment are probably responsible for the rapid dissemination of the disease through out the continent. Genetic and molecular studies of the biology of V cholerae have permitted identification of a variety of new virulence factors besides the enterotoxin, and are also helping to unravel the exquisite mechanisms that regulate the expression of these virulence factors in response to different stimuli. Molecular studies of V cholerae chromosomal and plasmid DNA, and of chromosomal and plasmid gene products, with techniques such as DNA hybridization and multilocus enzyme analysis are improving the characterization of V cholerae strains, resulting in progress in understanding their epidemiology in different communities. The non-invasive character of V cholerae infections, epidemiological and immunological studies suggest that the disease and current vaccines fail in providing an effective and long lasting immunity, and that the control of the disease in endemic areas by the use of vaccines may therefore be unfeasible. Similar studies indicate that the provision of safe drinking water, adequate sewage disposal, sufficient nutrition, and education remain the most effective measures for controlling the disease.

[A patient with AIDS: infection associated with pneumocystis carinii and cryptococcus neoformans]. / Paciente con SIDA: infeccion asociada por pneumocystis Carinii y cryptococcus Neoformans.

A patient with AIDS developed pulmonary infiltrates typical of infection by P. carinii. However, therapy for this agent was unsuccessful. Further studies including blood cultures revealed the presence of C neoformans. Specific therapy for this agent led to recovery. Concomitant opportunistic infections may cause diagnostic and therapeutic problems in patients with AIDS.

[Intestinal tuberculosis: analysis of clinical cases and autopsy]. / Tuberculosis intestinal: análisis de casos clínicos y autopsias.

Intestinal tuberculosis is rare compared to other forms of the disease. A review of the last 10 years in a General University hospital identified 21 cases diagnosed at autopsy and 8 during life. Most patients were males, older than 30 years of age, alcoholics and originating in southern Chile. Evidence of concomitant pulmonary tuberculosis was frequent. Disease was located most commonly at the ileum and cecum, and surgery was needed in a high proportion of cases. Hepatic cirrhosis and lymphopenia were common findings in autopsy patients.

[Transabdominal cerclage in the treatment of cervical incompetence]. / Cerclaje transabdominal en el tratamiento de la incompetencia cervical.

Six transabdominal cerclages in patients with cervical incompetence due to severe cervix damage or vaginal cerclage failure are presented. Results are discussed. In this series the salvage rate was 90%. For the first time in the literature a successful case of transabdominal cerclage in patient with a cervico-vaginal fistula is presented.