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Staphylococcus © Gram ive spherical once arranged in clusters ° Non sporing , non-motile , aerobic or facultative anaewbic come. ° Common inhabitant of the Skin & mucous membrane. © Causes localized Suppuvative. infection © Develop resistance to P & other Antibiotics —Nosocomical Chowital) infection . © Sir Alexander Ogston — Staphyle means bunch of grapes & kokkos mean berry like. CLASSIFICATION * 7 Based on pigmentation : ® S. Aureus produces gaden plot pagers (Rosen bach ) @ S. Albus produces white pigments QO S.Ccbvs produces lemon yellow Colonics. > Based on Coaqulaee Phodsletion : | | Le Coagulas< +e Staphylecoccun_ = pathleate Fg. S. aureuy _, S. hyicus » 8. intesmelinr. G Coagulax —ve Staplyldeoceua | — Commensals . E.g : S.epidermis , S- Saprophyticun . 7 Based on pathogencaty : one: aa een | L> Pathogenic — S.aurem , S-epidevmdes : S-Saprophytcus. Ls Non pathogenic — $.Capitis , 8-hominis. STAPHYLOCOCCUS AVREUS: => MORPHOLOGY - ° They art Gram +ve Sphenical cocci (1p) arranged. th Cluattr , may be geon in Singles , pairs & Short chains. ¢ Tey are non -motile , non spring & may We Capsulated . Scanned by £2] Camera Scanner => CULTURAL CHARACTERISTICS :. © Grow on basal media, at opt. temp ef 3A%c & pH of 4-4-7-6. They art aerobic & facultative anaewbic Cocci . -On nutvient agar (24his) — Colonies are large, smovth , Shiny , Opaque With golden Yellow pigments . — On Slope - Ott paint appearance . — On Blovd agar - § hemolytic Colonia are Sen. ~— Other Selechve media : ($-!0-/. NaCl) ew) Salt Milk agar Ludlang medium Mannitol salt agar Phenyl ethyl alcohol agar. => BIOCHEMICAL TEST ° 4. Catalase tut . tve | 2. Side Coagulese teot ~ +ve (soreening Rot for idenbf. ef S. aureus) 3. Tube Coaqulare teat : +ve Loonfirmatory ent) Cfor tdente. i S- aureus) 4. Mannitol fermentation ttst : fermen mannitel anaerbically . Other confirmatory +tot | — Production % phaphat > tve — Dnarse +tst — +ve — Thermonucleant tet —> tve | — Antibiotte Sensitivity tot — is impt.as tt helps ¢o guide in treatment a4 Staphylecacct readily producer veristance against anti biot'co => VIRULENCE FACTORS : > Cllwar Vuwence factors — - Protein fr — Atiphagecytic , Chemotactic & Anittcomplementary usd fer sevologial +eot ,Coagglutination tet. * Teithoic actd — helps (n adhewon of Cocci , Ant phagocyte + Peptidoglycan ~ Ackvalia C, induces velear a4 inflammatory cytokcnes . + Capswe — Ant phagocyhe Scanned by £2] Camera Scanner => PATHOGENESIS -° e Sourte of Infection — Carrier, Intected het. Node 04 Infection — direct by inhalaten , ingeshen , indcreck by formitty . > Staphylococcta produce 2 typ of diseaks ar (a) infections ,(b) Intoxication. > In infected , Cocci gain acces +h the damaged skin & mucesal ex tissue skide, colovused by adhenng do celly or ex traceilutar matrix , evade host oletence — i Mechanisms , Multiply & Cause tissue damage . , > Tm intoxication, the disease ts cauxd by the bactaial doxing ether produced in ‘the infedd hest ov preformed in vitn. ° STAPHYLOCCAL DISEMSES : RANGE FROM LOCALIZED To SYSTEMIC > LOCALIZED CUTANEOUS INFECTIONS — invade skin through wounds, follics eT gland, © Folliculih's —> Superficial intlammahon of hatr follicle , usually reolveo With No tompltcatiom but (an pngreg. @ Furuncle — Boil, inflammation 2 hair follicle oF Selacteous david progrenca into abcern . @) Carbuncle = es & Deeper lexion cluster oh Agubdel @ Impetigo — Bubble like swelling that Can break § peel away , mostty neuaberna. © Paronychia — Abces . 7 SYSTEMIC | © Musculo skelebl ‘abection => Oseomyelidts, Actwnitis Puisstiik. Pyomuyosihs. © Reopiratory Snfecton —> Tonsiliids , Pharyngitis, Sinusitis , OtiHg medéa. , | Bronche pneumonia, Lung abcess. © CNS 4ngection —> Brain Abcen, Meningitis o Endovascular Infection —> bacterimia , Septtcemia Pyeruia , bl benabd toe: = LABORATORY DIAGNOSIS : o Chiniwl Specimen — Pun [Swab > Suppurative lesions Sputum —> Reop, Snfect. . Blood —> Bacterimia , Lephcemia. Stool —r Food poisoning Scanned by 1. Camera Scanner ree MicRoscoPY — Gram +ve sphearital Cocci arranged in Guoteia along usith polymorpha Cuneful m Care “| pus ) => CUNLCAL CONCERNS & TREATMENT 4g |: have penicillinase & are regishant to penicillin Lother antbiohe umd iv horpitals . o MRSA — Methicillin resistant S. aurea — art rtristant t p-lactew Cmethitcillin) Prevention: > Hand hygiene 7 Tavlahen of dnfedid patent > Sertening of hospital personel . > Universal precautien by healthare providen d prevent infection: Other Staphy bococe: —_S. epidesmidis — lives en Skin & Mutcouy membrane . — cau evdocarditns , bacteremia, UTI. = 1S. Saprophy Hcus — infrequently lives en Skin , inttotine , vagina, UTI. Scanned by £9 Camera Scanner STREPTOCOCCUS PYOGENES: => MORPHOLOGY : > Gram +ve, spherical ox Oval cack arranged on Chain © Non mokle , Non gpvring > Some are. capsulated (young) => CULTURAL CHARACTERISTICS * © Ut is Srewbic /facultatie anaervbic , fastidious organism , 3°c , L4hs ,5-101-Co, Blood agar - Colonies are small ) lows Convex , B - hemoliyris is Seen. © Glucex | goxum broth — Turbidity with deport is Sen. => _ VIRULENCE FACTORS - 7 Antigenic Structure : () feptidoglycan — Pyogenie , Thrombolytic O. Grbohydrste — grrvping @® Protein — M protin— inhibit phagpoytoRis @ Fimbriae — Attochmerl a Cocci. | > Anhgenic Crom nen — O Gpswar hyalurnic acid & synovial fluid @ (elk wall protein §& myocardium ® Chg & Cardiac valves _ @ feptidogtycan € Stin fg SG) Cyn p aante membrane €, leer intima Responsible Pos differcxtk Streptrcoceal disearen. > Etntdlealbe Toxins. — Streptrlysins = Shrephlysa 0 - Lhe kb toate R rakdtd cove Aritigenic — ASD Tet CAaihe whewmachz feur) : Strepio lysin 8 — p- henrolyris . > Pyogente toxin Cexytnmgenic) — indirces fever & typical red vash Superantgenn — caw the veleax of Hssue necootc factwr (TNF) Priduscer — Sniflamrortory cytrkines Couring fever , tissue damage, Shock. Scanned by £2] Camera Scanner > Extracellular Enzyme » © Streptokinase — lysis of -fibrin clots , breaks -fibrin bayrier & plays a vole in Spread of infection. © DNiAax (Steptodomase) — depolymensation ef DNA reaponsible -for thin gerous exudsla . Therapeutically to Uquify thick enudak Ant - DNAanx B test — diagnosis ef Steeptpcoccal Skin infection . © Hyaluronidase — breaks down connective tissue, spread oF infection | © NADax. => PATHOGENESIS : © Humans only reseavoir © “nappropriat Casriexs. ° Transmission -— contact , dioplets , fomiteo . © Portal ef enty generally skin Or respiratmy tract ° Uuildven predominant group affeckd -for cutaneous & thrvat infections. ° Systemic infections € progression. 7 SUPPURATIVE INFECTION [upper Rt. tract infec) > Sore thynat (pharyngitis) — Common in School going childrerv.. Sore throat , fever, headache , malaise , erythematous & grayish vohite exudate . — Townlts, Foctal resh ¢ Mandibwar Lynpha denopathy . Ls Tonsillar abcess , Mrusitis , otitis media , ludwigs angina — Meningifis ,» preumonma are are. > SKIN & SOFT TISSUG INEECTION: Ls Tmpetigo (pyoderma) - superficc al cutaneous infectien - Crupt — Wn iM childrewm — Ag 4 Evyspdas § Cellulitis - pathogen onters tough a break in tne skin & wentually spreads fo deeper cutancinuy layer. Local tapflammetion qotth ocd , exythema , indiuroted lemon , fever , headache ¢ malaise. L, Necxotising fasciitis, myowtis — Mtype £223 (hte eating bachuta) excuniv necwovs o¢ fascia , Yheutansu £ Metocwlar Wee. - Dic, Shock —TSs Scannedbyf2}:Camera Scanner > Btochamwtcal Teal - © Catalan tot — tve o They art not soluble in bile Cio -f..) © Do not ferment Rihere. o PYR tot — caury hydrolysis 4 PYrroli olony| naph thylamiae . o Maxted’s teat + +ve — Badtwacin sunsitivity teyt S. pyogenes is Gunmtive tn bacitracin. © Raptd diagnostic tot Kit — Streptococcal arp A ant'gen can be detectad in thyat swab, = [LAB DIAGNOSIS OF Non SUPPURATIVE INFECTIONS : ° Specimen — Serum fo Diagnows a ARF Lael el o ASo ot — Titre > 200 unih 8s. Sigvuftcant (not usaetul — for _? “ AGN) eo oe AGN 2 pyodenma o Anti — DNAae deat / sti by duonidene tect ‘Titre 2 300 units & Signefrcant, ° Strepto Zyme tert o Passive hema golutination ttot . Scanned by £2] Camera Scanner 
