[Typhoid fever in school children: by what measures is the modification of the clinical course due to oral vaccination?]. / Fiebre tifoidea en escolares: en que medida la clinica es modificada por el uso de una vacuna oral?

The clinical course of infection by Salmonellae was compared between patients who had been vaccinated against typhoid fever using the Ty21a vaccine and those who had not. Of 2566 bacteriological confirmed cases 84% were infected with S typhi, 14% with S paratyphi B and 2% with S paratyphi A. Among patients with typhoid fever, 34% were treated in hospital, 3.5% had relapses, 5.4% developed complications and 1 patient died (0.05%). Among patients with paratyphoid fever, 18% were treated in hospital, 0.6% had relapses, 1.4% developed complications and there were no deaths. These figures were similar among vaccinated and non-vaccinated cases. A slightly greater proportion of vaccinated cases were treated in hospital (38 vs 30%). Thus, use of oral vaccination against typhoid fever does not alter the clinical course of infection with Salmonellae.

Molecular epidemiology of Haemophilus influenzae within families in Santiago, Chile.

Thirty-six consecutive patients with invasive Haemophilus influenzae type b (Hib) infections at Roberto del Rio Children's Hospital, Santiago, Chile, were enrolled in a prospective study. Throat cultures were obtained from household contacts of each index case, adjacent neighbors, and matched community control households. Colonization rates for H. influenzae were comparable among groups; however, among household contacts 18% of colonizing isolates were Hib, compared with 2% and 3% among neighbor and community controls. When selected isolates were evaluated further by outer membrane protein (OMP) profiles and multilocus enzyme electrophoresis, only one of the four Hib isolates from household members matched the corresponding index case isolate. One serologically nontypeable isolate from a household contact had an OMP profile and electrophoretic type identical to that of the corresponding Hib index case isolate; hybridization studies with a 9-kb capsular gene probe showed a profile consistent with a capsule-deficient mutant. Hib strains were isolated more frequently from household contacts than from control persons living in Santiago, but colonizing Hib strains were often unrelated to the index case strain.

[Paratyphoid B fever in 2 areas of Santiago. An analysis of the epidemiological significance]. / Fiebre paratifoidea B en dos áreas de Santiago. Un análisis de su significación epidemiológica.

Salmonella isolates from 3920 patients with typhoid fever from 2 areas in Santiago were analyzed to determine the frequency of association with S paratyphi B infection. This was demonstrated in 18.8% of subjects in both areas, a figure significantly higher than the 8-10% previously reported. The association with S paratyphi B was higher for females, especially for the younger age group. These findings suggest an infectious agent-gender-age interaction which may explain the discrepancy with previously reported rates of infection. Their possible relation to the chronic salmonella carrier state and association with biliary tract lithiasis and cancer is discussed.

Increasing resistance to trimethoprim-sulfamethoxazole among isolates of Escherichia coli in developing countries.

Resistance of Escherichia coli to trimethoprim (TMP)-sulfamethoxazole remains at 3%-8% at many medical centers within the United States. In this study a 44% resistance rate was observed among E. coli isolated at a pediatric hospital in Santiago, Chile, and a 40% resistance rate at a general teaching hospital in Bangkok, Thailand. Most isolates were from urinary tract infections and showed high-level resistance (minimal inhibitory concentration of TMP greater than 1,000 micrograms/ml). Nineteen of 35 isolates tested transferred resistance to TMP; most cotransferred resistance to streptomycin and sulfonamides. Dihydrofolate reductase type I was detected by gene probing in 14 of 35 strains. Subsequent investigations in Brazil, Honduras, and Costa Rica revealed that this high rate of resistance was not an isolated phenomenon.

Rotavirus en diarreas de evolucion prolongada. / Rotavirus in diarrheas of prolonged course

Dada la alta frecuencia de hallazgo de rotavirus en diarreas agudas, decidimos estudiar la participacion de este virus en diarreas de evolucion prolongada, que es una forma evolutiva menos frecuente y con multiples agentes causales. Se estudiaron 43 ninos menores de 1 ano hospitalizados en el Servico de Lactante del Hospital Roberto del Rio entre Septiembre de 1980 y Mayo de 1981, que evolucionaron con sindrome diarreico prolongado. Se investigo en las deposiciones la presencia de bacterias y parasitos por metodos habituales, y de rotavirus por la tecnica de ELISA indirecta. Ademas se estudio la presencia de intolerencia a disacaridos y de possibles focos infecciosos extradigestivos. Se encontro rotavirus en 46.5%, bacterias en 62.8%, parasitos enteropatogenos en 11.6%.Se encontro intolerencia a disacaridos en 55% de los lactentes rotavirus positivo y en 26% de los negativos, diferencia estadisticamente significativa. Se discute la importancia de los distintos agentes, con especial enfasis en el papel que juegan los rotavirus

Rotavirus viral RNA electrophoresis in hospitalized infants with diarrhea in Santiago, Chile.

Viral RNA electrophoresis technique was used to detect rotavirus in 226 children under 2 years of age with acute diarrhea, admitted to the Roberto del Río Hospital in Santiago, Chile, during the period of June 1979 through May 1980. A group of 50 children included in the aforementioned sample, admitted in winter, was compared with a control group of 25 infants without digestive pathology. In these groups, rotavirus was detected in 20 out of 50 children with diarrhea (40%) but not in the controls (0%). A positive diagnosis of rotavirus was found in 66 out of the total of 226 patients (29.2%); its monthly distribution ranged between a maximum of 83.3% (June) and a minimum of 11.1% (October).

[Pleural empyemas in children due to Hemophilus influenzae]. / Empiemas pleurales por Hemophilus influenzae en niõs.

22 consecutive cases of pleural empyema due to H. influenzae in children are reported. An increment of its incidence during the 1975-76 period is observed. All cases were in children under 3 years of age, with a mean of 15.5 months. The presenting syndrome at admission was varied. In 50% of cases, pleuropulmonary infection was ignored. Nearly one half of cases of pleural empyema due to H. influenzae had simultaneous purulent meningitis caused by the same microorganism. This type of empyemas, though having a prolonged evolution, apparently appear to have a good prognosis, compared with that produced by S. aureus. There are some differences, being the most outstanding: low frequency of pyoneumothorax and the lack of radiological evidences of abscesses and or pneumotoceles, in any phase of the clinical course. Stress is placed on the value of the bacteriological study of blood and CSF in children under 3 years of age with pleural empyema. A high rate of positive blood cultures was found. (75%). Pieuropulmonary complications, as a frequent event during severe infections (septicemic disease) due to H. influenzae is considered. A clinical characterization of children in whom a pleural empyema could occur is proposed. A discussion is made about diagnostic, therapeutic and prognostic implications of these complications.

[Cholestyramine in the treatment of acute bacterial diarrhea in infants]. / Colestiramina en el tratamiento de la diarrea aguda bacteriana del lactante.

32 infants admitted to Hospital "Roberto del Río" with infectious diarrhea and dehydration were assigned random to two groups, one of them receiving the usual therapeutic regimen of rehydration, refeeding and furazolidone and the other group the same treatment plus cholestyramine. The patients were studied with balance technique on days 1st, 3rd., and 5th. after admission, analyzing clinical progress, features of the stools, total digestive transit time, pH of the feces and the presence of reducing substances, volume of the stools, water excretion and sodium, potassium and chloride elimination in the feces. The patients receiving cholestyramine showed an earlier improvement in the appearance of the stools, less excretion of feces and water and diminished sodium and potassium elimination. Chloride excretion was similar in both groups. Cholestyramine tolerance was excellent. No side effects or complications were observed.