Biofilm inhibitors targeting the outer membrane protein A of Pasteurella multocida in swine

Pasteurella multocida (Pm) is the causative agent of atrophic rhinitis in swine. This study aimed to discover biofilm inhibitors against swine Pm to counteract antibiotic resistance and decrease virulence. The virulence factor outer membrane protein A (OmpA) was targeted. A library of drugs approved by the Food and Drug Administration (FDA) was used to perform virtual screening against PmOmpA. The top-scoring compounds had no effect on the growth of Pm serotype A or D. Mycophenolate mofetil showed the highest efficacy in inhibiting biofilm formation by Pm serotype A, with an IC₅₀ of 7.3 nM. For Pm serotype D, indocyanine green showed the highest effect at an IC₅₀ of 11.7 nM. Nevertheless, these compounds had no effect on an established biofilm of Pm. This study offers an alternative way to prevent biofilm formation by Pm that could also be applied to other pathogens.

Chronic nasal infection caused by Klebsiella rhinoscleromatis or Klebsiella ozaenae: two forgotten infectious diseases

OBJECTIVES

Klebsiella rhinoscleromatis and Klebsiella ozaenae are associated with chronic diseases of the upper airways: rhinoscleroma and ozena, respectively. These have become uncommon in developed countries. We report herein one case of each disease in patients living in Marseilles, France, and include a review of the literature.

METHODS

Diagnosis was made by direct evidence of bacteria (specific cultures and autoimmunohistochemistry on nasal biopsy) and using an indirect method (serology). In addition, the literature review showed that the majority of publications were old, confirming the fact that these diseases have been long forgotten.

RESULTS

The specific and original methods used have allowed us to confirm the pathogenic role of K. ozaenae in ozena and confirmed rhinoscleroma in a granulomatous lesion. In the literature, K. rhinoscleromatis is only associated with rhinoscleroma whereas K. ozaenae is also associated with clinical diseases other than chronic rhinitis.

CONCLUSIONS

In cases of chronic rhinitis, ozena and rhinoscleroma should be kept in mind, even in developed countries, and systematically screened for, especially as there are specific diagnostic tools and effective treatments available.

[Effect of aerosol therapy with cyclopheron in patients with chronic rhinitis]

Recently the number of patients with nasal cavity diseases has significantly increased mainly due to the chronic rhinitis. Due to the topical nature of the problem it is necessary to develop new methods of the treatment of chronic rhinitis and to use physiotherapeutic factors which have no side effects of chemotherapy. Total of 62 patients were investigated. 34 of these patients had chronic catarrhal rhinitis and 24 had chronic allergic rhinitis. It has been established that aerosol-therapy with cyclopheron has a considerable effect in patients with these forms of chronic rhinitis, right up to full normalization of their condition as well as on rhinoscopic data, particularly on the olfactory function and mucociliar clearance. Decrease of neutrophiles and eosinophiles present in the mucous discharged from the nasal cavity has a bacteriostatic action expressing in the decrease of size of colonies of microbial cultures.

[Successes and failures of ozena's medical treatment]

Ozena belongs to the primary atrophic rhinitis of unknow etiology. The incidence of this disease has markedly decrease in the last decades. We treated 4 patients with ozena between 2000-2005. The diagnosis was confirmed by physical and ENT examination, culture from the nose and CT scan of perinasal sinusis. Ciprofloxacin was aministrated orally in a dose 1,0-0,5 g daily to all patients. Also they were instructed how to clean the nose regularly with an isotonic saline solution and to moisteurse nosa by wotery spray. The treatment with ciprofloxacin was maintained for 4-6 weeks. In 3 causes the result was very good after 2-4 y observation. 1 patient, 16 y. old girl, didn't cooperate therapy propely - she stoped nasal rinsing after some improvement. The second course of treatment seems to get good result (3 months observation). Our and some other authors conclusion is: ciprofloxacin seems to be a promising drug for the treatment of ozena. For good results cleanising the nose regularly is importent as well as antibiotic.

[Comparison of the mucociliary transport rate of rhinitis sicca and atrophic rhinitis]

OBJECTIVE

To study the mucociliary transport function of rhinitis sicca and atrophic rhinitis, and to explore the standard of diagnosis.

METHOD

The MTR of normal control group, the rhinitis sicca group and the atrophic rhinitis were determined by using saccharin, and then compared. Then MTR of rhinitis sicca treatment group were compared before and after treatment.

RESULT

The MTR of normal group: (9.15 +/- 0.86) mm/min; the rhinitis sicca group: (5.84 +/- 0.48) mm/min and the atrophic rhinitis group: (3.36 +/- 0.07) mm/min. There were significant difference among them (P < 0.05). 25 patients of rhinitis sicca were treated by administering the pill of Gelomyrtol forte in 2 weeks. The MTR of rhinitis sicca were no significant difference before and after treatment (P > 0.05).

CONCLUSION

Rhinitis sicca is a separate nasal disease, which is different from atrophic rhinitis. It is important to find an effective treatment for the disease.

Interactions between the bioactive glass S53P4 and the atrophic rhinitis-associated microorganism klebsiella ozaenae

In an aqueous environment, ions are released from a bioactive glass (BAG) and the pH rises in its vicinity. This may influence both growth and colonization of microorganisms. We studied the effects of the BAG S53P4 on the atrophic rhinitis-associated microorganism Klebsiella ozaenae. The glass was used in the form of granules or discs. Growth inhibition was studied using an agar plate test. Adhesion was studied by incubating bacterial suspension with the glass. The effect of the presence of the bacteria on the formation of the Si-rich layer on the bioactive glass was also analyzed. Furthermore, a follow up study of 19-74 months with ozena patients surgically treated with the BAG S53P4 was performed. The bioactive glass showed no clear growth inhibition of K. ozaenae in the agar plate test. K. ozaenae showed low adherence to the BAG S53P4. No growth of the microbe was seen on the glass during the 8 h incubations and the Si-rich layer was formed normally. The clinical follow-up study showed no infections of the implants and the symptoms of the patients were markedly reduced. Thus, the BAG S53P4 did not favor adhesion and colonization of K. ozaenae, in vitro, which is supported by the in vivo findings showing no BAG-associated infections or reinfections.

Successful treatment of ozena with ciprofloxacin

Rhinitis chronica foetida, or ozena, is a rare chronic inflammatory disease. The aetiology and pathogenesis are still not satisfactory explained. For many years various medical and surgical methods for the treatment of this slowly progressive and disabling disease have been tried without permanent success so far. The new fluoroquinolones with excellent effect on gram-negative bacteria and high suitability for oral use offer a potentially attractive treatment for ozena. We review our experience in the treatment of 10 patients with ciprofloxacin in a daily dose of 500-750 mg b.i.d. for 1-3 months. The patients have been followed regularly for up to 26-74 months after treatment and in all of them we registered permanent disappearance of odour, crusting, and growth of Klebsiella ozenae. We conclude that ciprofloxacin provides a step towards better conservative therapy for patients with ozena.

Atrophic rhinitis: antibiotic treatment

Atrophic rhinitis is a term used to describe a rare nasal infection. Although it does not have a fatal outcome, cause osteomyelitis, or produce pain, it does induce bilateral nasal obstruction and a persistent foul odor of which the subject and others are painfully aware. The organism most often associated with atrophic rhinitis is Klebsiella ozenae. Antibiotic susceptibility patterns of this microorganism have made treatment with orally administered antibiotics difficult. K ozenae was cultured from the nasal cavity of three patients. Two patients were treated for two weeks with tobramycin (MIC, 4 micrograms/ml; 4 mg/kg/day). Odor decreased in one patient, but K ozenae failed to clear. In the second patient both odor and K ozenae disappeared. The third patient was treated for 1 week with tobramycin (MIC, 4 micrograms/ml; 4 mg/kg/day); odor decreased, but K ozenae could still be cultured. She was treated for an additional 2 weeks with topical gentamicin (MIC, 0.5 micrograms/ml) with disappearance of both odor and K ozenae. Intravenous aminoglycoside may be helpful in treating atrophic rhinitis, but topical aminoglycoside may provide an effective and cheaper form of treatment.

Medical therapy in rhinology

The treatment of nasal diseases is both medical and surgical. This article broadly reviews the medical treatment of the most common nasal pathologies.

Comparative efficacy of sulfamethazine and sulfathiazole in feed for control of Bordetella bronchiseptica infection in swine

Seventy-two conventionally raised pigs were challenge exposed intranasally when approximately 3.5 weeks old with yolk-grown Bordetella bronchiseptica. Twenty-four pigs acted as noninfected, nonmedicated controls. Feed containing sulfamethazine or sulfathiazole (110 mg/kg of feed) was initiated in 2 groups of 24 infected pigs each 3 days after challenge exposure and was fed continuously for 56 days. Twenty-four infected pigs were given nonmedicated feed. Challenge exposure with the B bronchiseptica resulted in nasal bordetellosis characterized by isolations of the test organism from nasal cavities of infected control pigs at greater than 90% frequency through 28 days and from at least 50% of the pigs through 56 days. Moderate turbinate atrophy developed with a 48% increase in mean turbinate space in infected control pigs at necropsy. Performance was not affected by the infection which was confined to the nasal cavity. The B bronchiseptica isolation rate decreased faster (P less than 0.01) in the sulfamethazine group than in the sulfathiazole group. By day 42, sulfamethazine-medicated pigs were negative for B bronchiseptica in nasal swab samples; whereas 8% to 17% of sulfathiazole-medicated pigs were positive from days 42 to 56. Turbinate spacing measurements averaged 11% less in the sulfamethazine group than in the sulfathiazole group.

Long-acting oxytetracycline for control of induced Pasteurella multocida rhinitis in swine

A long-acting oxytetracycline formulation was evaluated for control of rhinitis induced experimentally in pigs with a capsular type A, toxin-negative, low-passage strain of Pasteurella multocida. The pigs were 6 to 7 weeks old and were naturally infected with Haemophilus parasuis. The H parasuis infection was thought to predispose to establishment of P multocida in the nasal cavity. A long-acting oxytetracycline formulation was given IM at the rate of 20 mg/kg, 4 times at 5-day intervals. Medication reduced (P less than 0.05) the severity of turbinate atrophy and the proportion of pigs with P multocida and H parasuis in their nasal cavities. Numbers of colonies of P multocida and H parasuis isolated were also less in medicated pigs.

The ozena problem. Clinical analysis of atrophic rhinitis in 100 cases

One hundred cases of ozena were analysed. The majority of cases were youths (86%). 50% of 33 patients had abnormal menstruation. Löwenberg's bacillus were found in most cases. The middle concha was a frequent side of this affection in our series, 25 cases of accessory sinusitis were found by roentgenographic examination of 35 cases of atrophic rhinitis. 24 cases underwent a serum cholesterol test. This revealed hypocholesterolemia in cases (50%) with an average value of 73.6 mg/100 ml. A large dose of vitamin (12500-150000 U daily or injected vitamin A 50000 U i.m. every other day or water-soluble vitamin A 300000 U twice a week) was generally favourable in most cases. Streptomycin had a beneficial result in sensitive cases. Complete cure of the disease was expected from the combined treatment with vitamin A and streptomycin. No recurrence was found in the majority of cases over a 2-year period of follow-up studies.

Porcine atrophic rhinitis: a model for studying nasal physiology and pathophysiology

Porcine infectious atrophic rhinitis is a disease of swine which ought to be of considerable interest to rhinologists. We have reviewed some aspects of human atrophic rhinitis, and some aspects of etiology incidence, pathology and physiology of porcine infectious atrophic rhinitis. Swine with this nasal problem fail rather dramatically, to gain as much weight as unaffected animals. We have speculated on several reasons for this including altered nasal physiology and trigeminal reflexes and reduced olfaction. Photographs of infected pigs are included.

[Attempt at restoring the health of pigs suffering from atrophic rhinitis]

A group of 24 sows selected from herds affected by atrophic rhinitis was subjected to the study of the therapeutic effect of the administration of wide-spectrum antibiotics combined with an improvement of the zoohygienic conditions and with full-value nutrition in the pre-partal period and during lactation. It was found that the mentioned measures in sows before parturition and their housing in a sanitized farrowing house during treatment generally improved the health of the sows and enabled the rearing of healthy piglets. The mortality rate during rearing up to the age of 28 days was 12.5%. In the control group of piglets and sows the losses amounted to 29%; the clinical symptoms of rhinitis were found in 11% of the piglets already at the age of 28 days.

[The local treatment of ozaena with streptomycin and novocaine (author's transl)]

The essence of this treatment is the injection of a mixture of 250 mgm of streptomycin (5 ml) and novocaine 1% (5 ml) on alternate days. The 10 ml mixture was injected into the conchae and submucosally into the septum on either side. Cure generally required a total of 2--3 gm of streptomycin over 15--20 days. Review of 25 cases treated over the past 15 years showed that 44% became symptom free and "good" results occurred in another 40%. In 16% treatment proved ineffective. Rehabilation was manifest by relief of subjective symptoms and disappearance of crusting and foetor. Atrophy remained irreversible.