Rapid emergence of El Tor Vibrio cholerae resistant to antimicrobial agents during first six months of fourth cholera epidemic in Tanzania

110 El Tor Vibrio cholerae isolates from 102 patients with cholera between November, 1977, and March, 1978, during the early stages of the fourth epidemic of cholera in Tanzania had minimum inhibitory concentrations to tetracycline, chloramphenicol, nitrofurantoin, neomycin, ampicillin, and sulphadimidine determined. All isolates during the first month after the disease was recognised were fully sensitive to tetracycline, but 76% of isolates were resistant to the drug after five months of extensive use of tetracycline therapeutically and prophylactically in the country. Resistance to the five other antibacterial agents developed more slowly. Isolates from patients who failed to clear the organism from their stools or who had cholera soon after tetracycline prophylaxis had increased minimum inhibitory concentrations of the drug. Resistance did not develop in vivo. Although resistance to tetracycline readily developed following extensive use of the drug, such a resistance was not the only reason for failure of tetracycline treatment and prophylaxis. Mass chemoprophylaxis in the control of cholera should be discouraged unless evidence to the contrary becomes available.

Possible mode of action of toltrazuril: studies on two Eimeria species and mammalian and Ascaris suum enzymes

The anticoccidial properties of toltrazuril in Eimeria falciformis-infected mice were potentiated by the simultaneous application of pyrimethamine, trimethoprim, or sulfadimidine. The same drugs potentiate the effect of toltrazuril by killing E. tenella schizonts in chicken kidney-cell cultures. Activities of some enzymes of the respiratory chain, such as succinate-cytochrome C reductase and NADH oxidase and succinate oxidase from mouse liver, were reduced in the presence of toltrazuril. The same effects could be observed when the activities of NADH oxidase and fumarate reductase from the nematode Ascaris suum were determined in the presence of the drug. Vertebrate enzymes involved in pyrimidine synthesis, e.g., dihydrofolate reductase from chicken liver, were also affected by toltrazuril; however, this effect was 500 times weaker than that shown by pyrimethamine. Toltrazuril also showed an inhibitory effect on the dihydroorotate-cytochrome C reductase from mouse liver. Our results suggest that toltrazuril primarily affects the respiratory chain and secondarily, two enzymes involved in pyrimidine synthesis.

Micrococcal urinary-tract infections in young women

In a prospective study in young women, novobiocin-resistant subgroup-3 micrococci were the second commonest cause, after Escherichia coli; of acute urinary infections. Proteus mirabilis was the only other causative organism. Symptoms, pyuria, or possible aetiological factors were the same in micrococcal and coliform infections. The infecting micrococcus "biotype" was only rarely found among the normal flora of the genitourinary tract of young women, though other micrococci and staphylococci were commonly present. Evidently, the infecting micrococci are selectively pathogenic in the urinary tract. Micrococcal infections, like coliform infections; commonly followed sexual intercourse, but there was no evidence that the micrococci were sexually transmitted. The infecting biotype was rarely found in the male urethra or prepuce.

Efficacy of various anticoccidials against experimental porcine neonatal isosporosis

The efficacies of 20 mg/kg body weight (BW) of toltrazuril (Toltra) 2 days post-infection (dpi), 2 mg/kg BW of diclazuril 2 and 3 dpi and 200 mg/kg BW of sulphadimidine 2, 3 and 4 dpi were compared in a model for piglet isosporosis. Weight gain (first 4 weeks of life) and diarrhoea and oocyst excretion from 4 to 11 dpi were evaluated (10-12 piglets/group). Additionally, animals were killed and examined for pathohistological changes of the small intestines 5, 7, 11 and 14 dpi (n = 3 per group and time point) and lengths of the intestinal villi. Diarrhoea (semi-liquid or liquid faeces) was seen from 5 dpi in all groups except Toltra, and the differences in prevalence and intensity of diarrhoea were statistically significant (p < 0.05) between Toltra and the other groups, which were similar (trial 1). Oocyst excretion was greatly reduced in the Toltra group, which was also statistically significant for the mean and median excretion rates and the percentage of excreting piglets between Toltra and the other groups (p < 0.05). Weight gain was highest in Toltra (p < 0.05). Histopathology revealed mostly villous necrosis and atrophy in the small intestines except the duodenum, which peaked at 7 dpi, in all groups except Toltra. Between 5 and 11 dpi, the Toltra group had significantly longer villi than the other groups. Reduced weight gain and diarrhoea caused by Isospora suis was controlled by a single application of Toltra in the pre-patent period, while neither diclazuril nor sulphadimidine improved the clinical picture of isosporosis.

Prevalence and control of bovine cryptosporidiosis in German dairy herds

In a 5-year survey regarding its prevalence and importance in five German state veterinary laboratories Cryptosporidium was diagnosed annually in 19-36% of faecal samples either submitted to the laboratories or taken post mortem. In approximately half of the cases no other enteropathogens were detected. However, only 73% of 30 laboratories participating in a questionnaire survey routinely tested for this parasite, and the majority of researchers considered cryptosporidiosis to be of minor importance. In a placebo-controlled field study 152 suckling calves were treated daily against cryptosporidiosis either with sulfadimidine or with halofuginone (Halocur, Intervet) over 1 week. Treatment by oral drench started at the onset of diarrhoea in the herd. Oocyst excretion, faecal consistency and health status were recorded five times for a 3-week period. Oocyst excretion peaked 7-14 days in the placebo group after the onset of diarrhoea, and during that period prevalence and intensity of excretion were significantly lower in the halofuginone-treated group compared to the sulfadimidine and the placebo control groups. The health status (diarrhoea, dehydration) declined in all groups but was significantly (P<0.05-0.001) better in the halofuginone group in the first 2 weeks. Halofuginone effectively (P<0.05-0.001) reduced oocyst excretion and improved the health status of the treated animals, while sulfadimidine had no effect against Cryptosporidium.

Genital ulcers in Kenya. Clinical and laboratory study

Of 97 patients with genital ulcers attending a special treatment clinic in Nairobi, Kenya, 60 harboured Haemophilus ducreyi, four herpes simplex virus, and five Neisseria gonorrhoeae. Eleven patients had serological evidence of syphilis; of these one case was confirmed by darkfield microscopy. In the remaining cases no aetiological agent was identified. An enriched chocolate agar with vancomycin and serum was a useful medium for primary isolation of H ducreyi. Tetracycline was generally ineffective in the treatment of ulcers, but sulfadimidine was successful in almost 80% of cases.

Luminous vibriosis in rock lobster Jasus verreauxi (Decapoda: Palinuridae) phyllosoma larvae associated with infection by Vibrio harveyi

Studies were conducted to determine the cause of outbreaks of luminous vibriosis in phyllosoma larvae of the packhorse rock lobster Jasus verreauxi reared in an experimental culture facility. On 2 separate occasions mortalities of up to 75% over a period of 4 wk were observed in 4th to 5th and 8th to 10th instar phyllosomas at water temperatures of 20 and 23 degrees C, respectively. Affected larvae became opaque, exhibited small red spots throughout the body and pereiopods, and were faintly luminous when viewed in the dark. Histopathology showed that the gut and hepatopancreas tubules of moribund phyllosomas contained massive bacterial plaques. The hepatopancreas tubules of moribund larvae were atrophic and some contained necrotic cells sloughed into the lumen. Dense, pure cultures of a bacterium identified as Vibrio harveyi were isolated from moribund larvae. The disease syndrome was reproduced by in vivo challenge and V. harveyi was successfully reisolated from diseased larvae after apparently healthy larvae were exposed by immersion to baths of more than 10(4) V. harveyi ml(-1) at 24 degrees C. Injured larvae were more susceptible to infection than were healthy larvae. Survival of larvae experimentally and naturally exposed to V. harveyi was improved when antibiotics were administered via bath exposures.

Single-dose antimicrobial therapy for urinary tract infections in women

Single-dose antimicrobial therapy for uncomplicated urinary tract inductions in women has been reported and evaluated by several investigators. A review of the results of these studies suggest that amoxicillin, sulfisoxazole, and trimethoprim-sulfamethoxazole are effective single-dose regimens in this setting. These results should not be extrapolated to other populations, such as pregnant women or children, or to other antimicrobial agents. The limited data available suggest that cephalosporins are less effective than the regimens recommended. When the infecting organism is sensitive, failure to eradicate bacteriuria with one of these single-dose regimens may be indicative of a more invasive infection, perhaps in the kidney.

Serious interaction between cyclosporin A and sulphadimidine

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Clindamycin and sulphonamides in the treatment of ocular toxoplasmosis

Eight patients with active toxoplasmic retinochoroiditis were treated with clindamycin and a triple sulphonamide combination for a period of up to 6 weeks. In addition systemic prednisone was administered when the optic nerve or the macula was involved (6 of the 8 cases). In all cases we observed clinical improvement within 2 weeks. Visual acuity improved in all cases. Side effects of the treatment were observed in 2 cases. The follow-up period ranged from 8 to 22 months.

Antibiotics versus no treatment for toxoplasma retinochoroiditis

BACKGROUND

Acute toxoplasma retinochoroiditis causes transient symptoms of ocular discomfort and may lead to permanent visual loss. Antibiotic treatment aims primarily to reduce the risk of permanent visual loss, recurrent retinochoroiditis, and the severity and duration of acute symptoms. There is uncertainty about the effectiveness of antibiotic treatment.

OBJECTIVES

To compare the effects of antibiotic treatment versus placebo or no treatment for toxoplasma retinochoroiditis.

SEARCH METHODS

We searched CENTRAL (which contains the Cochrane Eyes and Vision group Trials Register) (2016, Issue 1), Ovid MEDLINE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid MEDLINE Daily, Ovid OLDMEDLINE (January 1946 to February 2016), EMBASE (January 1980 to February 2016), Latin American and Caribbean Health Sciences Literature Database (LILACS) (January 1982 to February 2016), the ISRCTN registry (www.isrctn.com/editAdvancedSearch), ClinicalTrials.gov (www.clinicaltrials.gov), and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We did not use any date or language restrictions in the electronic searches for trials. We last searched the electronic databases on 22 February 2016. We searched the reference lists of identified articles and contacted pharmaceutical companies for unpublished trials.

SELECTION CRITERIA

We included randomised controlled trials that compared any antibiotic treatment against placebo or no treatment. We excluded trials that included immunocompromised participants. We considered any antibiotic treatment known to be active against Toxoplasma gondii. Antibiotic treatment could be given in any dose orally, by intramuscular injection, by intravenous infusion, or by intravitreal injection.

DATA COLLECTION AND ANALYSIS

The primary outcomes for this review were visual acuity at least three months after treatment and risk of recurrent retinochoroiditis. Secondary outcomes were improvement in symptoms and signs of intraocular inflammation, size of lesion, and adverse events. We used standard methodological procedures expected by Cochrane.

MAIN RESULTS

Four trials that randomised a total of 268 participants met the inclusion criteria. In all four studies antibiotic was administered orally.One study conducted in Brazil in both adults and children compared trimethoprim-sulfamexacocol over 20 months to no treatment and was judged to be at high risk of performance, detection, and attrition bias. The other three studies compared antibiotic treatment to placebo. We judged these three studies to be at a mixture of low or unclear risk of bias due to poor reporting. One study conducted in the US in adults studied pyrimethamine-trisulfapyrimidine for eight weeks; one study conducted in the UK in children and adults evaluated pyrimethamine for four weeks; and one study conducted in Brazil in adults investigated trimethoprim-sulfamethoxazole for 12 months. In the last study, all participants had active retinochoroiditis and were treated with antibiotics for 45 days prior to randomisation to trimethoprim-sulfamethoxazole versus placebo.Only the study in Brazil of trimethoprim-sulfamethoxazole over 12 months, in participants with healed lesions, reported the effect of treatment on visual acuity. People treated with antibiotics may have a similar change in visual acuity compared with people treated with placebo at one year (mean difference -1.00 letters, 95% confidence interval (CI) -7.93 to 5.93 letters; 93 participants; low-quality evidence).Treatment with antibiotics probably reduces the risk of recurrent retinochoroiditis compared with placebo (risk ratio (RR) 0.26, 95% CI 0.11 to 0.63; 227 participants; 3 studies; I(2) = 0%; moderate-quality evidence); similar results were seen for acute and chronic retinochoroiditis.The UK study of pyrimethamine for four weeks reported an improvement in intraocular inflammation in treated compared with control participants (RR 1.76, 95% CI 0.98 to 3.19; 29 participants; low-quality evidence). The study in Brazil of trimethoprim-sulfamethoxazole for 12 months stated that the severity of inflammation was higher in the comparator group when compared to the antibiotic-treated group but did not provide further details. In the US study of pyrimethamine-trisulfapyrimidine for eight weeks intraocular inflammation had almost completely resolved by eight weeks in all participants, however in this study all participants received steroid treatment.Two studies (UK and US studies) reported an increased risk of adverse events in treated participants. These were a fall in haemoglobin, leucocyte, and platelet count, nausea, loss of appetite, rash, and arthralgia.

AUTHORS' CONCLUSIONS

Treatment with antibiotics probably reduces the risk of recurrent toxoplasma retinochoroiditis, but there is currently no good evidence that this leads to better visual outcomes. However, absence of evidence of effect is not the same as evidence of no effect. Further trials of people with acute and chronic toxoplasma retinochoroiditis affecting any part of the retina are required to determine the effects of antibiotic treatment on visual outcomes.

Treatment of ovine toxoplasmosis with a combination of sulphamezathine and pyrimethamine

Experimentally induced toxoplasmosis in pregnant ewes was treated with a combination of sulphamezathine and pyrimethamine. Fifteen untreated ewes gave birth to 14 live and six dead lambs whereas all the 15 lambs born to the 12 treated ewes were viable. The placental lesions were less severe, the gestation period was longer and the precolostral antibody titres to Toxoplasma gondii were lower, all significantly, for the lambs born to the treated ewes.

Retropharyngeal lymph node infection in horses: 46 cases (1977-1992)

A retrospective study of 46 horses with retropharyngeal lymph node (RPLN) infection presented to the Rural Veterinary Centre between 1977 and 1992 was undertaken. Horses aged less than one year were most commonly represented (46%). Thirty-nine percent of cases had been exposed to horses with confirmed or suspected strangles (Streptococcus equi subsp equi infection) within the previous 8 weeks. Most frequent signs were unilateral or bilateral swelling of the throat region (65%), respiratory stertor/dyspnoea (35%), purulent nasal discharge (20%), inappetence and signs of depression (15%), and dysphagia (9%). All horses had a soft tissue density in the retropharyngeal region on radiographs. Rhinopharyngoscopy, ultrasonography, haematology as well as cytological and microbial analysis of material aspirated from the soft tissue swelling facilitated diagnosis in some horses. Fifteen horses (33%) were treated with procaine penicillin intramuscularly for 4 to 7 days followed by oral trimethoprim-sulphadimidine for 7 to 14 days. Non-steroidal anti-inflammatory drugs were administered to 6 horses. Four required tracheostomy for severe respiratory distress. The 15 horses treated medically responded to treatment and were discharged from hospital. Three horses (6%) with mild signs received no treatment and recovered uneventfully. Twenty-eight horses (61%) underwent general anaesthesia and surgical drainage of a RPLN abscess. Nineteen received procaine penicillin G for 4 to 7 days. Four of the nine horses that did not receive antibiotic treatment after surgery required further surgical drainage 10 days to 7 weeks after the initial surgery. Limited follow-up information was available for 37 horses.(ABSTRACT TRUNCATED AT 250 WORDS)

Combination of trimethoprim with sulfonamides other than sulfamethoxazole

Early in the development of trimethoprim (TMP), the response to the drug was less than enthusiastic. Preliminary clinical trials were performed with sulfonamides that were unsuitable partners. On the basis of bacteriologic and pharmacokinetic evidence, sulfamethoxazole (SMZ) was chosen for the fixed-ratio (5:1) combination with TMP. Possible criteria on which to base the choice of a sulfonamide partner for TMP have been delineated. The theoretical considerations may be questioned in view of limited clinical experience with some combinations and lack of controlled comparisons in well-designed clinical trials with others. Objective proof of the clinical superiority of newer TMP-sulfonamide combinations over TMP-SMZ is required.

Prevention of Eimeria alabamensis coccidiosis by a long-acting baquiloprim/sulphadimidine bolus

Twelve calves aged 6-10 months, and 12 calves aged 10-16 months were turned out onto a permanent pasture known to have been contaminated with oocysts of Eimeria alabamensis during the previous year. Two days after turnout, six of the older calves and six of the younger were each treated with one bolus per 200 kg bodyweight containing 1.6 g baquiloprim and 14.4 g sulphadimidine. The other 12 calves were left untreated. The excretion of Eimeria oocysts, the faecal dry matter and the weight gain of treated and untreated calves within each age group were compared during the first 3 weeks on pasture to assess the efficacy of the bolus in preventing E. alabamensis coccidiosis. All the older of the untreated calves and four of the younger developed gruel-like to watery diarrhoea 4-7 days after turnout. The faecal consistency of the treated calves remained firm and they lost significantly less weight than the control calves during the first 13 days on pasture. The treated calves also excreted significantly fewer oocysts during the first 20 days of grazing; their oocyst excretion remained low during days 8-10 when all but one of the diarrhoeic control calves excreted more than 850,000 oocysts per gram faeces (OPG). Starting on days 12 to 14 the oocyst excretion of 8 of the treated calves increased to 20,000-65,000 OPG and of 2 calves to 210,000-240,000 OPG. There was no difference in oocyst output between treated and untreated calves from the fourth week of grazing and no difference in weight gain among the younger calves. In the older calves there was a tendency for the untreated calves to gain more weight than treated calves.