Rhodococcus equi fast facts

    G+ve , facultative intracellular (multiply inside macrophage).

          Can live in soil for approximately one year.

         High resistant to antimicrobial.

         Cause chronic pyogranulomatus pneumonia and enteritis sometimes including other organs like (Joint, spinal cord, lymph node, eye, liver, kidney,..).

         Can cause sudden death.

         Foal 1-6 months with clinical signs in 4-12weeks.

         Immunosuppressive micro-organism.

        Zoonotic especially with patient of aids.

         High mortality rate in foal sometimes reach to 80%.

         Decrease mortality firstly by erythromycin + rifampicin, 1997.

         Treatment with erythromycin and rifampin (10mg/kg po twice daily) should be continuing for

6-8 weeks.

         Recently by Azythromycin + rifampicin, 2000.

          Azythromycin 10mg/kg daily for 5 days followed by 3 doses with 48hrs intervals.

         Infection depends on immunity of foal.

-          Mice are carrier.

         Inhalation or digestion of large numbers of bacteria is a route of infection.

         Diagnosis: 1- CBC (high platlet) 2- Leukocytosis with neutrophilia 3- Fibrinogen (high) 4- Histopathol

ogy  5- cultivation 6- isolation 7- serology.

         X-rays and Ultrasound helpful in diagnosis.

          Postmortem (shows pyogranulomatus pneumonia).

         Crackling, wheeze auscultation in the both lung.

          Signs: 1- fever 2- Cough 3- mucopurulant nasal discharge 4- tachipenia 5- leathergy 6- depression 7- loss of body weight 8- dyspnea 9- lameness or ataxia.

     Prevalence of clinical signs 10-20% in endemic farms with mortality approximately 28%.

         Control: monitoring of fibrinogen, WBCs, Neutrophil, X-rays to detect early infection. Or using of (Rhodococcus equi hyper immune plasma) HIP in farms under risk or endemic with R.equi with good value.

          Control: Gallium maltolate orally (stop multiplication of bacteria and has anti-inflammatory effect) at the 1st 2weeks of life of good value.

          Control: high sanitation, hygiene (low dust, sand contaminated with feces).

Rhodococcus (Corynebacterium ) equi in camelids

R.equi affects also new world camelids (Hong and Donahue, 1995; Cuteri et al.,2001), but there were no reports of R.equi infection in old world camelids yet. Four cases of disseminated R. equi infection in adult breeding dromedaries occurred at one camel farm near Dubai within 16 months of each other (Kinne et al.,2011). At necropsy the lungs were diffusely consolidated with large caseous areas. Histology revealed sever suppurative to necrotizing pneumonia with multiple encapsulated abscesses. Immune-histochemistry enabled the detection of R.equi ant

igen in the lung section. High numbers of R.equi were isolated from the lung lesions as well as the liver, spleen and mediastinal lymph node. The isolated stains wre PCR- positive for the specific virulence plasmid of R.equi.

(J.Kinne and U.Werney) (Central Veterinary Research Laboratory CRVL), Dubai, UAE.

The Rhodococcus (Corynebacterium) equi  also found in lung, liver and spleen of a lama at University of California. (Medicine and Surgery of Camelids, Murray E. Fowler, 3rd edition

Treatment:

As shown in fast facts about treatment R.equi bacteria by Azythromycin and Rifampicin but now there is a new trend of treatment by using Tulathromycin (R/DRAXXIN – Pfizer) s.c injection 2.5 ml / 100 kg B.W one shot once per week, and the results were promising. (Monica  Venner, Regina Kerth, Erich Klug, University of veterinary medicine, Hannover, Germany, 11 Oct. 2006).

Draxxin injection