1. ACTINOMYCETES @ They are Gram positive bacteria, forming branching filaments like fungi. @ Contain the following genera: * Actinomadura: causes mycetoma * Streptmyces: causes mycetoma * Nocardia: causes mycetoma & bacterial infection * Actinomyces: causes bacterial infection

3. Nocardia @ Found as saprophytes in the soil. Infection occurs by inhaling spores. Species: @ N. brasiliensis: causes mycetoma @ N. asteroides: causes nocardosis

5. Nocardia asteroides Properties: @ Aerobes, with branching filaments, gram-positive, weakly acid-fast. @ N on-motile, non-sporing, catalase positive, urease positive. Nocardosis: @ It begins with pulmonary infection, then forms abscesses and sinuses. @ It spreads to the brain and kidneys.

7. Lab. Diagnosis of Nocardia asteroides @ Specimens: pus, sputum, tissues @ Microscopy: To see the gram-positive or weakly acid-fast and branching rods @ Culture: Incubate on Sabouraud medium for 3-14 days. It grows at 35-45°C and at room temp. Colonies are orange.

9. Actinomyces Properties: @ Non-motile, no spores, has branches @ Gram positive, Weakly acid fast, @ Has round, yellow (sulpher) granules @ Anaerobic & microaerophilic. @ Part of the normal flora of the mouth and female genital tract

11. Main species: Actinomyces israelii Disease: @ It causes actinomycosis @ A chronic, granulomatous infection @ It affects the jaws, face, neck, chest abdomen, pelvis, brain, and lungs. @ Sinuses occur, & pus containing sulpher granules is discharged

13. Laboratory Diagnosis of Actinomyces : Specimens:‘ Pus, sputum, tissue. Microscopy: gram-positive branching rods Culture: Inoculate the granules on blood agar, incubate for 5-7 days at 35-37°C. Colonies are creamy or white & rough. Identification: Catalase & indole negative urease negative, nitrates negative, aesculin hydrolyzed, lactose fermented @ Identification by immunofluorescence.

15. PROVIDENCIA Species: P. rettgeri and P. stuartii Properties: @ Gram negative rods, motile, aerobic and facultatively anaerobic @ Catalase positive, oxidase negative, non-lactose fermenter @ It is citrate positive, gelatin positive, urease negative, phenylalanine positive.

17. Diseases: @ Normal habitat is the human & animal intestines, sewage, soil, and water. @ May cause UTI, burns infections, and diarrhoea @ P. rettgeri causes nosocomial infections

19. MORGANELLA Species: Only one species: M. morganii Properties: @ Gram negative rods, motile, aerobic and facultatively anaerobic @ Catalase positive, oxidase negative, non-lactose fermenter. No swarming. @ Phenylalanine positive, urease positive, citrate negative, gelatin negative.

21. Diseases: @ M. morganii: found in human & animal intestines, sewage, soil, and water. @ It causes UTI, nosocomial infections, diarrhoea in infants. @ Morganella produces urease enzyme that hydrolyses urea in urine to form ammonia, which leads to alkaline urine & this causes formation of magnesium & ammonium stones

23. Diagnosis of Providencia & Morganella Specimens: Urine, sputum, swabs, blood. Microscopy: Gram negative rods, motile, Culture: Media: Mac Conkey, blood agar or CLED agar. Providencia swarms on blood agar and Morganella no swarming Biochemical Reactions: Lactose negative, catalase positive, oxidase negative by API

25. Species UreaCitIndSucH2SH2SPDAGG P.mirabilis +D--+++ P.vulgaris +D++++D M.morgani +-+--+D P.rettgeri ++++-DD P.stuarti-+++-+- Biochemical reactions of Proteus, Morganella, and Providencia species Key: Urea = Urease test, Cit = Citrate test, Ind = Indole test, Suc = Sucrose fermentation, H 2 S = Hydrogen sulphide production, PDA = Phenylalanine deaminase test, GG = Gas from glucose fermentation, D = Different strains give different results