Reemergence of Chloramphenicol Sensitivity in Enteric Fever

Background

Enteric fever is a global health problem and rapidly developing resistance to various drugs makes the situation more alarming. Drug sensitivity in Salmonella enterica serovar typhi and Salmonella enterica serovar paratyphi A isolated from 45 blood culture positive cases of enteric fever was tested to determine in-vitro susceptibility pattern of prevalent strains in northern India.

Methods

Strains isolated from 45 blood culture positive cases of typhoid and paratyphoid fever over a period of three years were studied and their sensitivity patterns to chloramphenicol, ampicillin, ciprofloxacin, ceftriaxone, nalidixic acid, amikacin and ofloxacin were analysed.

Results

Our results show a high sensitivity of both Salmonella enterica serovar typhi (96%) and Salmonella enterica serovar paratyphi A (100%) to chloramphenicol. Sensitivity to ciprofloxacin and amikacin was 88% and 84% respectively. All the isolates were sensitive to ofloxacin, nalidixic acid and ceftriaxone. Sensitivity of Salmonella enterica serovar paratyphi A was 100% to chloramphenicol, ciprofloxacin, ofloxacin, nalidixic acid and ceftriaxone, 95% to amikacin and 30% to ampicillin. Overall 44 out of 45 isolates of Salmonellae were sensitive to chloramphenicol.

Conclusion

These findings suggest changing pattern of antibiotic resistance in enteric fever with reemergence of chloramphenicol sensitivity in northern India.Key Words: Enteric fever, Chloramphenicol, Salmonella enterica serovar typhi, Salmonella enterica serovar paratyphi A     

Treatment of acute lymphoblastic leukemia in adults with intensive induction, consolidation, and maintenance chemotherapy

The Southwest Oncology Group conducted a study of acute lymphoblastic leukemia (ALL) in adults over a 5-year period, testing the utility of the L-10M regimen initially described by the group from Memorial Sloan- Kettering Cancer Center. One hundred sixty-eight eligible patients were treated with this intensive combination chemotherapy regimen. One hundred fifteen (68%) achieved complete remission. With the current median follow-up time of 34.5 months, the median durations of remission, relapse-free survival, and overall survival were 22.9, 20.9, and 17.7 months, respectively. Only 35% of the patients over 50 years of age achieved a complete remission. Age was a significant prognostic factor for complete response, survival, relapse-free survival, and remission duration. In addition, a low initial WBC count was found to have a statistically significant association with longer remission duration. Responders between the ages of 20 and 49 years with WBC counts of less than 15,000 appear to have an exceptionally good prognosis.     

Similarities of specificity and cofactor dependence in serum antiphospholipid antibodies from patients with human parvovirus B19 infection and from those with systemic lupus erythematosus

Objective. To assess the phospholipid specificity and immunoglobulin isotype of antiphospholipid (aPL) antibodies in patients with acute parvovirus B19 infection. Methods. Specificity of aPL and isotype distribution in the negatively charged phospholipids, cardiolipin and phosphatidyl serine, and in the neutral phospholipid, phosphatidyl ethanolamine, were measured in the sera of patients with acute parvovirus B19 infections (n = 12), in those with other acute viral infections (n = 10), and in those with syphilis (n = 15) by enzyme-linked immunosorbent assays. The dependence of anticardiolipin (aCL) binding on the presence of β₂-glycoprotein I (β₂-GPI) as a binding cofactor was assessed in these same groups, and was compared with sera from systemic lupus erythematosus (SLE) patients (n = 11) with raised aCL antibody reactivity. Results. Antibodies against any of the 3 phospholipids were found in all 3 groups of patients with infections (B19 in 11 of 12 patients, other viral infections in 8 of 10 patients, and syphilis in 14 of 15 patients). B19 patients' sera contained predominantly IgG antibodies against the negatively charged phospholipids, cardiolipin and phosphatidyl serine, and differed in their specificity and isotype distribution from those found in the other 2 patient groups. B19-associated aCL increased their binding to antigen in the presence of β₂-GPI as a binding cofactor, similar to aCL found in SLE patients, but unlike antibodies from patients with other viral infections or from those with syphilis. Conclusion. The results show the remarkable similarity in specificity of aPL antibodies between B19-infected patients and SLE patients, and raise the question of whether parvovirus infection may be a trigger for the development of aPL antibodies in autoimmune diseases.