Title General systemic stated - Localized infection.pdf ✅

GENERAL SYSTEMIC STATES Prepared by Dr. Hussam Mohamed Mohamed Ibrahim Professor of Internal Medicine Faculty of Veterinary Medicine Department of Internal medicine and Infectious Diseases Internal Medicine – General Program – 4th Level Students
LOCALIZED INFECTIONS An infection is the invasion of tissues by pathogens, their multiplication, and the reaction of host tissues to the infectious agent and the toxins they produce. Localized infections are common in farm animals and many are bacterial infections secondary to traumatic injuries. Because most of them have a surgical outcome, by incision and drainage or by excision or amputation, they are not usually included in medical textbooks. They are presented briefly here because of their importance in the differential diagnosis of causes of toxemia and also because of their space-occupying characteristics, which cause compression of other structures. Also, the initial treatment is often medical, especially if the location of the lesion cannot be identified. Faculty of Veterinary Medicine Department of Internal medicine and Infectious Diseases Internal Medicine – General Program – 4th Level Students
Etiology Abscesses and similar aggregations of pyogenic material in certain anatomic locations include pharyngeal, submandibular, retroperitoneal, hepatic, splenic, pulmonary, cerebral, pituitary, spinal cord, and subcutaneous abscesses. Other similar lesions include embolic nephritis, guttural pouch empyema, lymphadenitis, pharyngeal phlegmon, osteomyelitis, tooth root abscesses, and infections of the umbilicus and associated vessels. More widespread accumulations of necrotic/toxic pyogenic debris occur and are described under the headings of pericarditis, pleurisy, peritonitis, metritis, mastitis, meningitis, and pyelonephritis. Faculty of Veterinary Medicine Department of Internal medicine and Infectious Diseases Internal Medicine – General Program – 4th Level Students
Other pyogenic lesions worthy of note include the following: 1. Inguinal abscess in horses. Some of these probably originate as post-castration infections, but some obviously have other origins, possibly as a lymphadenitis arising from drainage of a leg with a chronic skin infection. 2. Traumatic cellulitis and phlegmon in soft tissue, especially skeletal muscle. The neck is a common site of infection in the horse, with lesions resulting from infected injection sites or the injection of escharotic materials, e.g., iron preparations intended only for intravenous administration. Penetrating traumatic wounds, often severely infected are among the serious occurrences to the legs and hooves of horses and cattle. These commonly penetrate joint capsules, bursae, and tendon sheaths, and underrun periosteum. Faculty of Veterinary Medicine Department of Internal medicine and Infectious Diseases Internal Medicine – General Program – 4th Level Students