1 / 44

STREPTOCOCCI

STREPTOCOCCI. General character. Gram positive cocci arranged in chains Catalase test negative Fastidious Facultative anaerobes Penicillin sensitive (Streptococcus faecalis ) Resistant to AG (GENTAMICIN ) . GROUP A STREPT. STREPTOCOCCUS PYOGENES. Most important pathogen

afra
Download Presentation

STREPTOCOCCI

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. STREPTOCOCCI

  2. General character • Gram positive cocci arranged in chains • Catalase test negative • Fastidious • Facultative anaerobes • Penicillin sensitive (Streptococcus faecalis ) • Resistant to AG (GENTAMICIN )

  3. GROUP A STREPT STREPTOCOCCUS PYOGENES

  4. Most important pathogen • Distinguished by bacitracin test (sensitive) • Some are capsulated (hyaluronic acid)

  5. epidemiology • Acquired through infected respiratory droplet • Direct contact _ Skin , hand • Indirect contact _contaminated objects • Spread enhanced by poverty overcrowding poor ventilation

  6. Source of infection A - Patient with active disease – tonsillitis • Convalescent carriers – throat B - Asymptomatic carriers (20% -school children ) – throat • Prevalent in children – 3 – 8 yrs

  7. VIRULENCE FACTORES A- CELL ASSOCIATED 1- M protein (antiphagocytic) - originates from cytoplasmic membrane produces protective type specific abs 2- lipoteichoic acid adhesion factor for attachment 3- hyaluronic acid capsule - antiphagocytic

  8. 3- STREPTOKINASE (fibrinolysin) • Thrombotic disease – coronary thrombosis 4- DNAases A , B , C , D. • AntiDNAase B - DIAGNOSE SKIN infections 5- HYALURONIDASE – spread factor 6- LIPOPROTEINASE – opacity factor

  9. B- EXTRACELLULAR PRODUCTS B- EXTRACELLULAR PRODUCTS 1- SREPTOLYSINS OR HAEMOLYSIN • Streptolysin o antigenic , ASO , oxygen labile • Streptolysin s oxygen stable, non antigenic 2- Erythrogenic toxin (SPE ) • SUPERANTIGEN • Bacteriophage – 3 types , A – B- C . • SCARLET FEVER

  10. DISEASESA - SAPURATIVE A- SAPURATIVE 1- TONSILITIS / PHARINGITIS 2- PERITONSILAR ABSCESS(QUINSY) 3- OTITIS MEDIA 4- ADENITIS 5- IMPETIGO (PYODERMA) 6- SCARLET FEVER 7- CELLULITIS 8- PUERPERAL SEPSIS 9- INVASIVE SOFT TISSUE INFECTIOS NECROTISING FASCITIS , MYOSITIS , TSS 10 - BACTERIMIA

  11. B-NON SUPPURATIVE (DELAED SEQUELAE) B- NON- SUPPURATIVE (DELAYED SEQUELAE) 1- RHEUMATIC FEVER : autoimmune disease follows throat infection only recur (M – SEROTYPES) 2- ACUTE GLOMERULONEPHRITIS Ag – Ab complexes May follow both throat or skin infection NO recurrence

  12. LABORATORY DIAGNOSIS SPECIMEN THROAT SWAB PUS WOUND BLOOD ASPIRATES SERUM – SEROLOGY : ASO TITRE

  13. MICROSCOPY • GRAM – STAIN • GRAM-POSITIVE COCCI IN CHAIN • USELESS IN THROAT SWAB

  14. CULTURE - IDENTIFICATION • BLOOD-AGAR (AEROBIC- ANAEROBIC) • BETA- HAEMOLYSIS (COMPLETE ) • ID • BACITRACIN SENSITIVITY • LANCEFIELDS GROUPING (CELL WALL CHO-Ag) • STREPTEX

  15. SEROLOGY • ASO-TITRE • RHEUMATIC FEVER • ACUTE GLOMERULONEPHRITIS • Anti-DNAase B • RECENT GROUP -A INFECTIONS (SKIN)

  16. TREATMENT • PENICILLIN – 10 DAYS • ALLERGY- • ERYTHROMYCIN • CEPHALOSPORINS • CEPHRADIN • CEFUROXIME

  17. GROUP C AND G STREPT. • SORE THROAT • SKIN INFECTION • WOUND INFECTION • SOFT – TISSUE • GENITAL – INFECTION • CELLULITIS • SEPTICAEMIA

  18. GROUP-B STREPTOCOCCUS(SREPT. AGALACTIAE) • RESERVOIR- COLON (RECTUM) • 10-40 % FEMALE . CARRIER (VAGINA) • 70% - NEOBORN – COLONISED DURING BIRTH • < 1% GET INVIASIVE INFECTION

  19. DISEASES A – EARLY ONSET (24 – 48 h ) RISK – FACTORS RUPTURED MEMBRANES (>18h PREMATURITY PROM (< 37 WEEKS) MULTIPLE BIRTH (TWINS) LOW BIRTH WEIGHT

  20. CLINICAL PICTURE • RESPIRATORY DISTRESS SYNDROME • SEPTICAEMIA • MENINGITIS • MORTALITY :

  21. B- LATE – ONSET HOSPITAL- AQUIRED (NOSOCOMIAL) MENNGITIS IN FULL – TERM NEONAT. BETTER PROGNOSIS MORTALITY

  22. DIAGNOSIS • CLINICAL • LATEX – AGGLUTINATION • CULTURE • ID • CAMP – TEST • STREPTEX (GROUPING)

  23. INFECTIONS IN ADULTS • POST-PARTUM SEPSIS • CHORIOAMNIONITIS • IMMUNOCOMPROMISED • SEPSIS • CELLULITIS • ARTHRITIS • PNEUMONIA

  24. TREATMENTPREVENTION • PENICILLIN OR AMPICILLIN + GENTAMICIN • SCREEN- PREGNANT W. (35-37 W) • CARRIER – PROPHYLAXIES • IV- PENICILLIN – AT LABOUR

  25. GROUP – D STREPT.NORMAL INTESTINAL FLORA A- ENTEROCOCCI GROW IN 40% BILE-ACID,6.5% NACL PENICILLIN RESISTENT AMPICILLIN SENSITIVE - E. FAECALIS : 80% - 90% INFECTI. - E. FAECIUM : MANY AMPICILLIN R. B- NON-ENTEROCOCCI PENICILLIN SENSETIVE STREPT . BOVIS

  26. DISEASES • URINARY TRACT INFECTIONS • ENDOCARDITIS • WOUND INFECTIONS TREATMENT AMPICILLIN + GENTAMICIN VANCOMYCIN ( VRE )

  27. ALPHA – HEMOLYTICSTREPTOCOCCI S.PNEUMONIAE VIRIDANS

  28. PNEUMONIA BACTEREMIA MENINGITIS SEPTIC ARTHRITIS PERITONITIS OTITIS MEDIA SINUSITIS CONJUNCTIVITIS BRONCITIS S.PNEUMONIAE

  29. GRAM POSITIVE DIPLOCOCCI • POLYSACCHARIDE CAPSULES (85) • ANTIPHAGOSITIC • OPSONIZING ANTIBODIES • ANTCAPSULAR AB. ARE PROTECTIVE • PNEUMOLYSIN

  30. RISK FACTORS • CEREBRAL IMPAIRMENT • VIRAL INFECTION • OLD AGE • HEART FAILURE • SPLENECTOMY • SCA , MULTIPLE MYLOMA , HIV • SKULL FRACTURE

  31. DIAGNOSIS SPUTUM , BLOOD , CSF • MICROSCOPY • QUELLUNG REACTION • BILE SOLUBLE • OPTOCHIN SENSETIVE • BLOOD CULTURE + IN 15% • LATEX AGGLUTINATION • SENSETIVITY TEST

  32. CEFTRIXONE + VANCOMYCIN PENICILLIN ERYTHROMYCIN CLINDAMYCIN VACCIN TREATMENT , PREVENTION

  33. VIRIDANS • NORMAL FLORA • OROPHARYNX • SKIN • GIT

  34. ENDOCARDITISFEVER , ANEMIA , HEART MURMUR • S. MUTANS –POLYSACCHARIDES (DEXTRAN) – DENTAL CARIES • S.SANGUIS • S.SALIVARIUS • S.MITIS • S. BOVIS ( CA. COLON ) • S.INTERMEDIUS ( MILLERI) • DENTAL , BRAIN , ABDOMINAL ABSCESSES

More Related