Pancreatic beta cell function persists in many patients with chronic type 1 diabetes, but is not dramatically improved by prolonged immunosuppression and euglycaemia from a beta cell allograft.

AIMS/HYPOTHESIS: We measured serum C-peptide (at least 0.167 nmol/l) in 54 of 141 (38%) patients with chronic type 1 diabetes and sought factors that might differentiate those with detectable C-peptide from those without it. Finding no differences, and in view of the persistent anti-beta cell autoimmunity in such patients, we speculated that the immunosuppression (to weaken autoimmune attack) and euglycaemia accompanying transplant-based treatments of type 1 diabetes might promote recovery of native pancreatic beta cell function. METHODS: We performed arginine stimulation tests in three islet transplant and four whole-pancreas transplant recipients, and measured stimulated C-peptide in select venous sampling sites. On the basis of each sampling site's C-peptide concentration and kinetics, we differentiated insulin secreted from the individual's native pancreatic beta cells and that secreted from allografted beta cells. RESULTS: Selective venous sampling demonstrated that despite long-standing type 1 diabetes, all seven beta cell allograft recipients displayed evidence that their native pancreas secreted C-peptide. Yet even if chronic immunosuppression coupled with near normal glycaemia did improve native pancreatic C-peptide production, the magnitude of the effect was quite small. CONCLUSIONS/INTERPRETATION: Some native pancreatic beta cell function persists even years after disease onset in most type 1 diabetic patients. However, if prolonged euglycaemia plus anti-rejection immunosuppressive therapy improves native pancreatic insulin production, the effect in our participants was small. We may have underestimated pancreatic regenerative capacity by studying only a limited number of participants or by creating conditions (e.g. high circulating insulin concentrations or immunosuppressive agents toxic to beta cells) that impair beta cell function.

Frequency of recovery of Blastocystis hominis in clinical practice.

We examined the frequency of isolation of Blastocystis hominis from stools of patients seen in an indigent-care teaching hospital. Over a 2-year period, 2,744 stool specimens were examined prospectively. B. hominis was found in 262 stools (9.5% of all stool specimens and 53.5% of the positive specimens). Clinical data were obtained from 80 patients with stools positive for B. hominis. B. hominis was the only parasite isolated in 39 of 47 (83%) of the adults, compared with 17 of 33 (52%) of the children (p = 0.006). All but 2 of 52 patients without concomitant parasitic infection or bacterial pathogens in stool had gastrointestinal symptoms (41 abdominal pain, 26 diarrhea, and 5 vomiting), but no association was seen with fever, peripheral leukocytosis, stool occult blood, fecal leukocytes, or endoscopic or radiologic evidence of colitis. Therefore, B. hominis was frequently recovered from stools examined in a hospital clinical parasitology laboratory. The clinical presentations of patients in our series did not suggest that B. hominis was invasive. Most patients with B. hominis probably do not require treatment since they will either have spontaneous resolution of symptoms or will be found to have an alternative explanation for their problem.

Disseminated Salmonella arizona infection associated with rattlesnake meat ingestion.

Salmonella arizona is an uncommon enteric pathogen. We report a case of a woman with systemic lupus erythematosus, receiving prednisone therapy, who developed fatal disseminated S. arizona infection after ingesting raw dried rattlesnake meat as a form of treatment for her illness. S. arizona was isolated from stool, blood, peritoneal fluid, and cerebrospinal fluid. The importance of being aware of the Mexican-American folk remedy involving the ingestion of rattlesnake meat in the forms of dried snake, snake powder, or snake powder capsules, and the risk of acquiring S. arizona enteric infections is discussed.

Spontaneous bacterial peritonitis due to Campylobacter coli.

A patient with alcoholic liver disease and ascites who developed fatal spontaneous bacterial peritonitis due to Campylobacter coli is reported herein. This is the first case report of spontaneous bacterial peritonitis due to this organism. Campylobacter infections and their relationship to spontaneous bacterial peritonitis are reviewed.

Brucellosis: atypical presentation with abdominal pain.

A patient with an atypical presentation of brucellosis is reported. The principal complaints of fever and abdominal pain did not initially suggest this diagnosis although a careful social history revealed the patient to be at risk of developing this infrequently reported infection. The gastrointestinal and hepatic manifestations of brucellosis are reviewed.

Vitamin B6-dependent Streptococcus mimicking fungi in a patient with endocarditis.

A patient was referred to our hospital with a tentative diagnosis of fungal endocarditis based upon clinical symptoms, suggestive travel history, and microscopic visualization in blood cultures of gram-negative bulbous filaments that appeared to be fungal elements. Subcultures of the blood culture bottles were unsuccessful on all media with the exception of blood agar plates, which had been cross-streaked with Staphylococcus aureus. These plates grew vitamin B6-dependent streptococci. This nutritionally variant organism was determined by biochemical tests to be Streptococcus mitis (mitior). It had a penicillin MIC and MBC of 0.015 micrograms/mL and 0.03 micrograms/mL, respectively and streptomycin MIC and MBC of 0.78 micrograms/mL and 1.56 micrograms/mL, respectively. The patient was treated with these two agents and recovered. We stress the importance of suspecting vitamin B6-dependent streptococci, even when gram stains may suggest presence of other microorganisms.

Protective studies with a group A streptococcal M protein vaccine. II. Challange of volenteers after local immunization in the upper respiratory tract.

Twenty-one adult volunteers were immunized at monthly intervals with three doses of purified type 1 M protein of group A Streptococcus. The soluble vaccine in buffer was administered by aerosol spray into the nares and oropharynx; 23 control subjects received a buffer placebo in the same manner. Antibody responses were observed in sera and nasal washings of some but not all vaccines. Approximately 30 days after the last dose, all subjects were challenged with homologus streptococci applied by swab to the phayngeal-tonsillar areas. In a double-blind system of evaluation, physical signs and symptoms were followed for assessment of infection. Illness was defined on the basis of a positive throat culture, fever, a twofold increase in white blood cell count over baseline, exudative pharyngitis, and cervical adenopathy. By these criteria four vaccinees and 11 controls were obviously ill. One vaccinee and six controls were questionably ill, fulfilling some but not all of the criteria. sixteen vaccinees and six controls were not ill (P less than 0.001). Positive throat cultures were observed in five vaccines and 19 controls (P less than 0.001). Penicillin was administered five days after challenge. No poststreptoccal sequelae or other complication were observed. Thus local immunization with M protein apparently can prevent both colonization and clinical illness after challenge with homologous streptococci.

Group A streptococcal M protein vaccine: protection following immunization via the respiratory tract.

Previous studies have shown the efficacy of parenteral immunization of volunteers with purified type 1 M protein against challenge with homologous streptococcui (J. clin, Invest. 52: 1885, 1973). A double-blind study was conducted on 21 adults immunized by aerosol-spray into the nasopharynx, and 23 controls who received saline placebo. Two booster doses were given at monthly intervals and approximately 30 days later vaccinees and controls were challenged with homologous streptococci (10-6/ml) by swabbing the pharyngeal-tonsillar areas. Throat cultures, leukocyte counts, temperatures and physical signs and symptoms were followed to assess infection. Illness was defined as a positive throat culture, oral temperature of larger than or equal to 38 degrees C, a WBC count of twice baseline or greater than 10,000 per mm-3, exudative pharyngitis and adenopathy. Of the 43 subjects, 13 were ill by all criteria (10 controls, 3 vaccinees [p smaller than .02]); 21 were well by all criteria (6 controls and 15 vaccinees); and 10 exhibited some but not all positive criteria (7 controls, 3 vaccinees). Positive throat cultures following challenge were obtained in 19 controls and 5 vaccinees (p smaller than 0.001). There was no correlation between the pre-challenge serum antibody titer and the development of subsequent illness. It is concluded that local topical immunization with a M protein vaccine offers significant type-specific protection against challenge with streptococci.