Evaluation of trimethoprim-sulphamethoxazole compound in treatment of salmonella infections

Comparative trial of Co-trimoxazole and Chloramphenicol in Typhoid Fever

A comparative trial of co-trimoxazole and chloramphenicol was conducted in two groups of 50 patients each to try to resolve conflicting opinions on the relative merits of the two drugs in the treatment of typhoid fever. We conclude that in our part of India co-trimoxazole is superior to chloramphenicol and that differences in our findings to those of others may perhaps be accounted for by differences in strains of Salmonella typhi, ethnic differences, and possibly differences in herd immunity to typhoid.

Management of enteric fever with amdinocillin

Twenty-six patients with enteric fever treated with amdinocillin and/or its pivaloyloxymethyl ester in 1975 to 1978 were compared with 21 patients with enteric fever treated with trimethoprim-sulfamethoxazole in 1972 to 1974. Diagnosis was based on clinical illness and isolation of Salmonella typhi or S. paratyphi A/B from blood cultures or stool cultures. The dosage of pivamdinocillin in adults was 400 to 800 mg, every 6 hours, for 10 to 16 days; dosage in children was half this amount for 11 to 15 days. Of the 21 patients treated with trimethoprim-sulfamethoxazole, 18 (86 percent) showed a satisfactory clinical response; 13 of these 18 had negative stools immediately after therapy, and two more were negative at the time of discharge (total: 83 percent). Mean hospital stay of these patients was 34.5 days. Of the 26 patients treated with amdinocillin, 23 showed a satisfactory clinical response; 20 of those responding clinically were still excreting the causative organism at the end of therapy; seven of the group remained as convalescent patients who continued to excrete the causative organism in feces at the time of discharge. Mean hospital stay was 43 days. The results of initial trials of amdinocillin and ampicillin in combination suggest that such therapy may be preferable to use of amdinocillin alone, although the excretion of the causative organism during convalescence has not been adequately assessed.

The combination of pivmecillinam and pivampicillin compared to co-trimoxazole in the treatment of enteric fever

Typhoid fever is an infectious disease with multisystem involvement and is commonly seen in the tropics. Twelve patients with acute typhoid fever were successfully treated with a fixed dose combination of pivmecillinam and pivampicillin. The treatment results were compared to those obtained from the treatment of ten other patients with co-trimoxazole, which is the routine treatment of our Department. The two forms of treatment appeared to be equally effective, suggesting that the combination mecillinam/ampicillin may represent a valuable alternative to the antityphoidal drugs currently available. Eleven patients were infected with strains resistant in vitro to either ampicillin, chloramphenicol, or both. All clinical isolates were sensitive to co-trimoxazole and to the combination of mecillinam and ampicillin. MIC values for the combination ranged from 0.16 to 2.5 mg/l. No side-effects were recorded.

Therapy of antimicrobial-resistant typhoid fever

Antimicrobial-resistant typhoid fever in Saigon was studied by examining in vitro antimicrobial susceptibilities of Salmonella typhi strains and conducting a randomized clinical trial of ampicillin and trimethoprim-sulfamethoxazole (TMP-SMZ). Isolates of S. typhi were obtained from blood or stool cultures of 90 patients. Of 87 isolates tested for antimicrobial susceptibility, 65 (75%) were resistant (R) to chloramphenicol, streptomycin, sulfonamide, and tetracycline, and 22 (25%) were susceptible (S). The drug resistance was transferable to Escherichia coli and was found in 11 different Vi-phage types. All isolates were susceptible to ampicillin and to TMP-SMZ. Agar dilution studies of TMP and SMZ showed synergistic inhibition of growth in all 18 S isolates and in 12 of 48 R isolates tested. The clinical trial of ampicillin and TMP-SMZ showed that both drugs were equally effective. Treatment failure with both drugs was more frequent in patients with S isolates than in patients with R isolates. Therefore, in an area where antimicrobial-resistant typhoid fever exists, patients with R isolates should receive either ampicillin or TMP-SMZ, but patients with S isolates should be treated with chloramphenicol.

Salmonella meningitis treatment with intravenous trimethoprim

Intravenous trimethoprim and sulphadiazine were used in the successful treatment of Salmonella meningitis in a four months old child. Pharmacological data are presented which show good penetration of the bloodbrain barrier by trimethoprim. This combination appears to be a useful alternative therapy for gram-negative meningitis.

Treatment of salmonella carriers with trimethoprim-sulfamethoxazole

One hundred and two patients with salmonellosis were observed, as either acute cases or asymptomatic carriers, over a span of 6 years. Twenty-eight patients were treated with antibiotics only or received no treatment; those in the treated group became negative for the infecting organisms after a mean time of 160 days, as compared with a mean of 52.4 days for those who were not treated. Seventy-four other patients were treated with frimthoprim-sulfamethoxazole (TMP-SMX) as the sole medication or after prior antibiotic therapy. Sixty of these patients (81.1%) were free from Salmonella in the mean time of 19.2 days, whereas 14 failed to respond and the condition cleared spontaneously in a mean time of 134.9 days. The poor response to treatment with TMP-SMX by children 2 years of age and younger is noted. The beneficial effects of treatment with TMP-SMX, as compared with antibiotics or no treatment at all, are examined in the light of the need to protect the public from this potentially dangerous infection.

Pharmacokinetics and efficacy of trimethoprim-sulfamethoxazole in the treatment of gastroenteritis in children

In vitro studies indicates that the constitutents of the drug combination co-trimoxazole are synergistic against Salmonella and effective against shigella isolated from children ill with gastroenteritis. The drug is well absorbed in children with gastroenteritis due to a variety of causes and is distributed, excreted and metabolized in a manner similar to that seen in normal adult volunteers. The drug is tolerated well by children with gastroenteritis even in very high dosages. Despite its in vitro and pharmacokinetic advantages, co-trimoxazole was not any more efficient than any other durg or no therapy in the treatment of salmonella gastroenteritis; it seems to have a role, however, in the treatment of typhoid fever and may be life-saving in patients infected with ampicillin- and chloramphenical-resistant strains. It is also effective in the treatment of shigella gastroenteritis and is recommended where ampicillin-resistant strains are encountered. Its potential usefulenss for the treatment of other bacterial causes of gastroenteritis in children must be evaluated by further controlled therapeutic trials.

Co-trimoxazole compared to chloramphenicol in the treatment of enteric fever

Co-trimoxazole (trimethoprim-sulphamethoxazole combination) was effective in the control of the acute infection in 60 patients with proven enteric fever. The mean interval between initiating treatment and defervescence was similar to that observed with a comparable group of 38 patients treated with chloramphenicol. Both co-trimoxazole and chloramphenicol were well tolerated and no serious adverse reactions, attributed to either drug, were noted. Two patients treated with chloramphenicol relapsed. No relapses were noted in the co-trimoxazole treated group. Although the evidence available at present in inadequate for drawing final conclusions regarding the relative efficacy of these two therapeutic agents in enteric fever, co-trimoxazole should be considered as an alternative drug, particularly when encountering salmonella strains resistant to chloramphenicol and ampicillin.

Antibacterial drugs today. I

Since the development of the sulphonamides in the 1930s and the subsequent development of antibiotics from the 1940s onwards, there have now been many drugs developed which are capable of chemotherapeutic activity in a patient infected by a susceptible micro-organism. This review is concerned with precise descriptions of important groups of antimicrobial drugs, with emphasis being placed on the more recently developed drugs. With each group of drugs the pharmacology, major therapeutic indications, dosages and adverse reactions are discussed. Part I of the article discusses the sulphonamides, the natural and semi-synthetic penicillins, cotrimoxazole, chloramphenicol, tetracyclines, the macrolides, lincomycin and clindamycin, fusidic acid, and the urinary antiseptics. The place of each in therapy is defined.

In vitro sensitivity of Salmonella to ten antimicrobial agents including sulfamethoxazole and trimethoprim, alone and in combination

The activities of trimethoprim (TMP) and sulfamethoxazole (SMZ), alone and in combination (SMZ-TMP), and of the following antibiotics were tested against 115 clinical isolates of nontyphoid Salmonella species: tobramycin, gentamicin, ampicillin, amoxicillin, neomycin, kanamycin, chloramphenicol, and tetracycline. The methods of disk diffusion, microtiter broth dilution, and agar dilution were employed for all single antimicrobial agents as well as for SMZ-TMP studies. Growth curves were performed in broth. SMZ-TMP, TMP, gentamicin, tobramycin, and neomycin were the most active drugs in vitro. All strains were inhibited by </=1 mug of TMP per ml, but >100 mug of SMZ per ml was required for at least 10% of strains. SMZ and TMP in a ratio of 10:0.5, respectively, inhibited all isolates and were synergistic for 105 strains. All strains inhibited by the combination of 10:0.5 SMZ-TMP had a zone diameter of >/=22 mm by using a combination disk containing 1.25 mug of TMP and 23.75 mug of SMZ. Seven isolates were resistant to >100 mug/ml of ampicillin or amoxicillin; all isolates were sensitive to chloramphenicol at </=6.3 mug/ml. SMZ-TMP appears to be active against nontyphoid salmonellae in vitro; this is usually due to a synergistic effect.

Toxicity of co-trimoxazole in nutritional haematinic deficiency

A woman of 47 habituated to analgesics and living on an inadequate diet was deficient in iron, folate and vitamin B₁₂. Treatment of pyelonephritis with co-trimoxazole precipitated pancytopenia with a megaloblastic bone marrow. She recovered following withdrawal of the drug and administration of iron, folate and vitamin B₁₂.