BAKTERI ANAEROBMORFOLOGI, FISIOLOGI, EPIDEMIOLOGI, DIAGNOSIS, PEMERIKSAAN

Sy. Miftahul El J.T

Figure 4-1 Catabolism of proteins, polysaccharides, and lipids produces glucose, pyruvate, or intermediates of the tricarboxylic acid (TCA) cycle and, ultimately, energy in the form of adenosine triphosphate (ATP) or the reduced form of nicotinamide-adenine dinucleotide (NADH).Downloaded from: StudentConsult (on 20 October 2009 07:04 AM) 2005 Elsevier

Oksigen berdasarkan keperluan oksigen dibagi dalam 5 kelompok

GroupEnvironmentO2 EffectAerobicAnaerobicObligate AerobeGrowthNo growthRequired (utilized for aerobic respiration)MicroaerophileGrowth if level not too highNo growthRequired but at levels below 0.2 atmObligate AnaerobeNo growthGrowthToxicFacultative Anaerobe (Facultative Aerobe)GrowthGrowthNot required for growth but utilized when availableAerotolerant AnaerobeGrowthGrowthNot required and not utilized

BAKTERI ANAEROB GRAM POSITIP BERSPORA[CLOSTRIDIUM spp]Genus ini meliputi kuman berbentuk batang pleimorf, spora lebih besar dari badan kuman, anaerob obligatGram-positive rods capable of forming endospores was placed in the genus Clostridium. This genus was defined by four properties: (1) presence of endospores, (2) strict anaerobic metabolism,(3) inability to reduce sulfate to sulfite, and (4) Gram-positive cell wall structure

The organisms are ubiquitous in soil, water, and sewage and are part of the normal microbial flora in the gastrointestinal tracts of animals and humans. Most clostridia are harmless saprophytesThe majority of infections seen today are skin and soft-tissue infections, food poisoning, and antibiotic-associated diarrhea and colitis. The remarkable capacity of clostridia to cause diseases is attributed to their ability to survive adverse environmental conditions through spore formation; rapid growth in a nutritionally enriched, oxygen-deprived environmentproduction of numerous histolytic toxins, enterotoxins, and neurotoxins.

SpeciesHuman DiseaseFrequencyC. difficileAntibiotic-associated diarrhea, pseudomembranous colitisCommonC. perfringensSoft-tissue infections (e.g., cellulitis, suppurative myositis, myonecrosis, gas gangrene), food poisoning, enteritis necroticans, septicemiaCommonC. septicumGas gangrene, septicemiaUncommonC. botulinumBotulismUncommonC. tetaniTetanusUncommonC. tertiumOpportunistic infectionsUncommonC. baratiiBotulismRareC. butyricumBotulismRareC. clostridioformeOpportunistic infectionsRareC. histolyticumGas gangreneRareC. innocuumOpportunistic infectionsRareC. novyiGas gangreneRareC. sordelliiGas gangreneRareC. sporogenesOpportunistic infectionsRare

Clostridium tetaniDifferential diagnosaKuman berbentuk panjang langsing, agak bengkok, Gram +/P, ukuran 4,8 x 0,5, tunggal atau berbentuk rantaiSpora bulat, terminal [seperti pemukul genderang], tidak berkapsul dan motilSuhu pertumbuhan optimum 370C dan pH 7,4Tumbuh baik pada media agar darah dengan zona hemolisa alfa kemudian menjadi beta akibat pembuatan hemolisin [tetanolisin]

Toksin, membentuk 3 jenis toksin :Hemolisin [tetanolisin]Termolabil, tidak tahan terhadap oksigen, bekerja aktif pada SDM dari sebagian besar binatang[ kelinci, kuda dll]Peran belum jelas mungkin bekerja sebagai lekosidinNeurotoksin [tetanospasmin]Tahan terhadap oksigen dan diinaktifkan pada 660C selama 5 mnt. dapat dibuat toksoid dengan penambahan formaldehid konsentrasi rendahBekerja seperti striknin dengan menghambat sintesis dan pelepasan asetilkolin sehingga menganggu transmisi neuromuskuler. Zat ini akan terikat kuat pada ganglion otak menyebabkan penghambatan neuron spinal pasca sinaps dengan mencegah pelepasan perantara penghambat [inhibitory mediator] kejang otot menyeluruh, reflek yang berlebihan dan serangan kejang berulang.Neurotoksin non-spasmogenik yang bekerja di saraf perifer

Gram stain of Clostridium tetani. Note the terminal spores.Downloaded from: StudentConsult (on 20 October 2009 07:04 AM) 2005 Elsevier

Clostridium tetaniPatogenesisKuman tidak bersifat invasif, akan tetap diluka, dapat menjadi bentuk vegetatif bila kondisi mendukung/anaerob, misalnya adanya: Jaringan nekrotikGaram kalsiumKuman piogenikBeberapa jenis tetanus :Tetanus neonatorum : akibat pencemaran luka pemotongan tali pusat bayi, angka kematian tinggiTetanus pasca keguguran dan masa nifas; akibat Infeksi saluran kelamin oleh alat bantu persalinan dan pembalutSplanchnic tetanus: terjadinya kekejangan otot otot menelan dan pernafasanCephalic tetanus: luka di daerah kepala akan terjadi kontraksi otot otot muka unilateral dan bilateral

Facial spasm and risus sardonicus in a patient with tetanus. (From Cohen J, Powderly WG: Infectious diseases, ed 2, St Louis, 2004, Mosby).Downloaded from: StudentConsult (on 20 October 2009 07:04 AM) 2005 Elsevier

A child with tetanus and opisthotonos resulting from persistent spasms of the back muscles. (From Emond RT, Rowland HAK, Welsby P: Colour atlas of infectious diseases, ed 3, London, 1995, Wolfe.)Downloaded from: StudentConsult (on 20 October 2009 07:04 AM) 2005 Elsevier

Clostridium tetaniDiagnosa laboratoriumPemeriksaan mikroskopis: sampel diambil dari luka, diwarnai Gram +/P seperti pemukul genderangBiakan: potongan jaringan nekrotik dibiakkan pada kaldu daging/agar darahPercobaan binatang : untuk melihat toksigenitas kuman, digunakan mencit yang disuntikan 0,2 ml suspensi kuman pada pangkal ekor, kemudian dilihat mulai terjadinya kekejangan Pencegahan & pengobatanPembersihan lukaImunisasi aktif dengan toksoidImunisasi pasif dengan ATSPemberian antibiotik :Penicillin

PENCEGAHAN TETANUS PADA LUKA

Keadaan lukaKeadaan kekebalanKebalKebal sebagianTidak kebalBersih [kecelakaan rumah dlm 6 jam1 x toksoid1 x toksoid3 x toksoidTercemar [tanah, ada jaringan nekrotik]1 x toksoid1 x toksoidATS, Antibiotik3 x toksoidATS, AntibiotikTerinfeksi1 x toksoidAntibiotik1 x toksoidAts, Antibiotik3 x toksoidATS, Antibiotik

Catatan :Kebal :Artinya telah menerima dosis lengkap berupa 3 x penyuntikan toksoidKebal sebagian :artinya telah menerima 2 x suntikan toksoidTidak kebal : artinya belum menerima toksoid atau keadaan kekebalan tidak diketahui

Clostridium perfringensDahulu dikenal C. welchii, merupakan salah satu penyebab ganggren gas, keracunan makanan oleh enterotoksin yang termolabil atau enteritis nekrotikC. perfringens can be associated with simple colonization or can cause life-threatening disease. C. perfringens is a large (0.6 to 2.4 1.3 to 19.0 m), rectangular, Gram-positive rod , with spores rarely observed either in vivo or after in vitro cultivation. This organism is one of the few nonmotile clostridia, but rapidly spreading growth on laboratory media (resembling the growth of motile organisms) is characteristic (GAMBAR 2). The organism grows rapidly in tissues and in culture, is hemolytic, and is metabolically active, features that make possible its identification in the laboratory. The production of one or more major lethal toxins by C. perfringens (alpha [], beta [], epsilon [], and iota [] toxins) is used to subdivide isolates into five types (A through E; TABEL). Type A C. perfringens causes most of the human infections in the United States.

Gram stain of Clostridium perfringens.Downloaded from: StudentConsult (on 20 October 2009 07:04 AM) 2005 Elsevier

GAMBAR 2. Growth of Clostridium perfringens on sheep blood agar. Note the flat, spreading colonies and the hemolytic activity of the organism. A presumptive identification of C. perfringens can be made by detection of a zone of complete hemolysis (caused by the ;-toxin) and a wider zone of partial hemolysis (caused by the ;-toxin), combined with the characteristic microscopic morphology.Downloaded from: StudentConsult (on 20 October 2009 07:04 AM) 2005 Elsevier

Distribution of Lethal Toxins in Clostridium perfringens Types A to E

TypeLethal ToxinsAlphaBetaEpsilonIotaA+---B+++-C++--D+-+-E+--+

Growth of Clostridum perfringens on egg-yolk agar. The ;-toxin (lecithinase) hydrolyzes phospholipids in serum and egg yolk, producing an opaque precipitate (right). This precipitate is not observed when the organism is grown in the presence of antibodies against the toxin (left). This reaction (Nagler's reaction) is characteristic of C. perfringens.Downloaded from: StudentConsult (on 20 October 2009 07:04 AM) 2005 Elsevier

Virulence FactorsBiologic Activity-ToxinLethal toxin; phospholipase C (lecithinase); increases vascular permeability; hemolysin; produces necrotizing activity, as seen in myonecrosis-ToxinLethal toxin; necrotizing activity-ToxinLethal toxin; permease-ToxinLethal binary toxin; necrotizing activity; adenosine diphosphate (ADP) ribosylating-ToxinHemolysin-ToxinHeat- and oxygen-labile hemolysin; cytolytic-ToxinCollagenase; gelatinase; necrotizing activity-ToxinProtease-ToxinHyaluronidase-ToxinDeoxyribonuclease; hemolysin; necrotizing activityEnterotoxinAlters membrane permeability in ileum (cytotoxic, enterotoxic); superantigen

Pada ganggren gas, karbohidrat akan dihancurkan dengan pembentukan gas karena ada septikemia, terjadi hemolisis intravaskuler.Pada keracunan makanan, enterotoksin merangsang enzim adenylate cyclase pada dinding usus bertambahnya konsentrasi cAMP hipersekresi air dan Cl dalam usus menghambat reabsorpsi Na Diare [selama 1-3 hari]

Diagnosa laboratoriumSpesimen dari luka, pus, jaringan atau makananMikroskopis: Gram +/P, batang tanpa sporaBiakan: di tanam pada agar tioglikolat, agar darah secara an aerob

PengobatanPembersihan luka secara bedah pada jaringan nekrotikAntibiotik : PenisilinHyperbaric oxygen

Clostridial cellulitis. Clostridia can be introduced into tissue during surgery or by a traumatic injury. This patient suffered a compound fracture of the tibia. Five days after the injury, the skin became discolored and bullae and necrosis developed. A serosanguineous exudate and subcutaneous gas were present, but there was no evidence of muscle necrosis. The patient had an uneventful recovery. (From Lambert H, Farrar W, editors: Infectious diseases illustrated, London, 1982, Gower.)Downloaded from: StudentConsult (on 20 October 2009 07:04 AM) 2005 Elsevier

Clostridium botulinumTerdapat secara luas di alam, kadang terdapat pada feses binatangC. botulinum, the etiologic agent of botulism, is a heterogeneous group of large (0.6 to 1.4 3.0 to 20.2 m), fastidious, spore-forming, anaerobic rodsBerdasarkan sifaT biokimia ada 2 jenis : Proteolitik [jenis A, B dan F], jenis sakarolitik dan tidak proteolitik [Jenis C, D, dan E ] semua jenis kelompok ini menghasilkan sulfidaDosis letal untuk manusia : 1 mikrogramTidak menyebabkan infeksi luka, tetapi menyebabkan keracunan makanan, akibat toksin yang termakan. Umumnya makanan yang tercemar adalah makanan yang berbumbu, diasap, kalengan tanpa dimasak terlebih dahulu.Kerja toksin akan memblokir pembentukan/pelepasan acetyl cholin pada hubungan saraf otot sehingga terjadi kelumpuhan otot.Gejala 18-96 jam makan toksin dengan keluhan penglihatan, hal ini terjadi karena tidak ada koordinasi. Sulit menelan, sulit bicara. Kematian terjadi karena paralisis otot pernafasan atau kelumpuhan jantung [cardiac arrest]Other species of clostridia produce botulinum toxins, including C. butyricum (type E toxin), C. baratii (type F toxin), and Clostridium argentinense (type G toxin). Human disease has only rarely been associated with C. butyricum and C. baratii, and not definitively demonstrated with C. argentinense.

Clostridium botulinum Classification and Toxin Production

GroupNeurotoxin TypePhenotyptic PropertiesIA, B, FProteolytic, saccharolyticIIB, E, FNonproteolytic, saccharolyticIIIC, DWeakly proteolytic, saccharolyticIVGWeakly proteolytic, asaccharolytic

Diagnosa laboratorium : mendeteksi toksin yang ada didalam serum penderita atau dari sisa makanan. Pendeteksian dilakukan dengan reaksi Netralisasi antigen-antibodi secara agglutinasi SDM yang dilapisis antiserum. Percobaan mencit yang disuntikkan bahan tersangka.Pengobatan:Pemberian antitoksin polivalen [tipe A,B dan C] secara IV dan secara simptomatik terutama untuk pernafasanPencegahan: Makanan yang diawetkan harus dimasak dahulu secara baik, makanan yang perlu diperhatikan : Kacang-kacangan, jagung, ikan asap atau ikan segar dalam plastik

Clostridium botulinum

Clostridium botulinum

CLOSTRIDIUM DIFFICILEUntil the mid-1970s the clinical importance of C. difficile was not appreciated. This organism was infrequently isolated in fecal cultures and its role in human disease was unknown. Systematic studies now clearly show, however, that toxin-producing C. difficile is responsible for antibiotic-associated gastrointestinal diseases , ranging from a relatively benign, self-limited diarrhea to severe, life-threatening pseudomembranous colitis (GAMBAR).

Antibiotic-associated colitis: gross section of the lumen of the colon. Note the white plaques of fibrin, mucus, and inflammatory cells overlying the normal red intestinal mucosa.Downloaded from: StudentConsult (on 20 October 2009 07:04 AM) 2005 Elsevier

Antibiotic-associated colitis caused by Clostridium difficile. A histologic section of colon shows an intense inflammatory response, with the characteristic "plaque" (black arrow) overlying the intact intestinal mucosa (white arrow). (Hematoxylin and eosin stain.) (From Lambert HP, Farrar WE, editors: Infectious diseases illustrated, London, 1982, Gower.)Downloaded from: StudentConsult (on 20 October 2009 07:04 AM) 2005 Elsevier

. Virulence Factors Associated with Clostridium difficile

Virulence FactorBiologic ActivityEnterotoxin (toxin A)Produces chemotaxis; induces cytokine production with hypersecretion of fluid; produces hemorrhagic necrosisCytotoxin (toxin B)Induces depolymerization of actin with loss of cellular cytoskeletonAdhesin factorMediates binding to human colonic cellsHyaluronidaseProduces hydrolytic activitySpore formationPermits organism's survival for months in hospital environment

ANAEROB, GRAM POSITIP, TIDAK MEMBENTUK SPORAThe anaerobic gram-positive cocci and non- spore-forming rods are a heterogeneous group of bacteria that characteristically colonize the skin and mucosal surfaces. These organisms are opportunistic pathogens, typically responsible for endogenous infections and usually recovered in mixtures of aerobic and anaerobic bacteria.Most of these anaerobes have fastidious nutritional requirements and grow slowly on laboratory media. Thus the isolation and identification of individual strains are difficult and often time consuming.

Important Anaerobic Gram-Positive Bacteria

OrganismHistorical DerivationAnaerobic CocciAnaerococcusan, without; aer, air; coccus, berry or coccus (anaerobic coccus)FinegoldiaNamed after the American microbiologist S. FinegoldMicromonas Peptostreptococcusmicro, tiny; monas, cell (tiny cell) pepto, cook or digest (the digesting streptococcus)SchleiferellaNamed after the German microbiologist K.H. SchleiferAnaerobic RodsActinomycesaktinos, ray; mykes, fungus (ray fungus referring to the radial arrangement of filaments in granules)Bifidobacteriumbifidus, cleft; bakterion, small rod (a small clefted or bifurcated rod)Eubacteriumeu, good or beneficial (a beneficial rod; that is, a rod normally present)Lactobacillusacto, milk (milk bacillus; organism originally recovered in milk; also, lactic acid is the primary metabolic product of fermentation)Mobiluncusmobilis, capable of movement or being active; uncus, hook (motile, curved rod)Propionibacterium propionicumpropionic acid (propionic acid is the primary metabolic product of fermentation)

ACTINOMYCESActinomyces organisms are facultatively anaerobic or strictly anaerobic, gram-positive rods. They are not acid-fast (in contrast to the morphologically similar Nocardia species), They grow slowly in culture, and they tend to produce chronic, slowly developing infections. They typically develop delicate filamentous forms or hyphae (resembling fungi) in clinical specimens or when isolated in culture (GAMBAR. However, these organisms are true bacteria in that they lack mitochondria and a nuclear membrane, reproduce by fission, and are inhibited by penicillin but not antifungal antibiotics. Numerous species have been described; Actinomyces israelii, Actinomyces meyeri, Actinomyces naeslundii, Actinomyces odontolyticus, and Actinomyces viscosus are responsible for most human infections. Only A. meyeri is a strict anaerobe. The other species grow best in anaerobic conditions but can grow aerobically.

Macroscopic colony (left) and Gram stain (right) of Actinomyces.Downloaded from: StudentConsult (on 20 October 2009 07:04 AM) 2005 Elsevier

PATHOGENESIS AND IMMUNITY Actinomyces organisms colonize the upper respiratory, gastrointestinal, and female genital tracts. These bacteria are not normally present on the skin surface. The organisms have a low virulence potential and cause disease only when the normal mucosal barriers are disrupted by trauma, surgery, or infection. Disease caused by actinomyces is termed actinomycosis (in keeping with the original idea that these organisms were fungi or "mycoses"). Actinomycosis is characterized by the development of chronic granulomatous lesions that become suppurative and form abscesses connected by sinus tracts. Macroscopic colonies of organisms resembling grains of sand can frequently be seen in the abscesses and sinus tracts. These colonies, called sulfur granules because they appear yellow or orange, are masses of filamentous organisms bound together by calcium phosphate (GAMBAR).

Sulfur granule collected from the sinus tract in a patient with actinomycosis. Delicate filamentous rods (arrow) are seen at the periphery of the crushed granule.Downloaded from: StudentConsult (on 20 October 2009 07:04 AM) 2005 Elsevier

EPIDEMIOLOGY Actinomycosis is an endogenous infection with no evidence of person-to-person spread or disease originating from an external source, such as soil or water. Disease is classified according to the organ systems involved. Cervicofacial infections are seen in patients who have poor oral hygiene or have undergone an invasive dental procedure or oral trauma. In these patients, the actinomyces that are present in the mouth invade into the diseased tissue and initiate the infectious process.

Patients with thoracic infections generally have a history of aspiration, with the disease becoming established in the lungs and then spreading to adjoining tissues. Abdominal infections most commonly occur in patients who have undergone gastrointestinal surgery or have suffered trauma to the bowel. Pelvic infection can be a secondary manifestation of abdominal actinomycosis or may be a primary infection in a woman with an intrauterine device (Central nervous system infections usually represent hematogenous spread from another infected tissue, such as the lungs.

TREATMENT, PREVENTION, AND CONTROL

Treatment for actinomycosis involves the combination of surgical dbridement of the involved tissues and the prolonged administration of antibiotics. Actinomyces are uniformly susceptible to penicillin (considered the antibiotic of choice), erythromycin, and clindamycin. Most species are resistant to metronidazole, and the tetracyclines have variable activity. The clinical response is generally good even in patients who have suffered extensive tissue destruction. Maintenance of good oral hygiene and the use of appropriate antibiotic prophylaxis when the mouth or gastrointestinal tract is penetrated can lower the risk of these infections.

Propionibacterium Propionibacteria are small gram-positive rods often arranged in short chains or clumps They are commonly found on the skin (in contrast with the actinomyces), conjunctiva, external ear, and in the oropharynx and female genital tract. The organisms are anaerobic or aerotolerant, nonmotile, catalase positive, and capable of fermenting carbohydrates. The two most commonly isolated species are Propionibacterium acnes and Propionibacterium propionicus.

P. acnes is responsible for two types of infections: (1) acne (as the name implies) in teenagers and young adults and (2) opportunistic infections in patients with prosthetic devices (e.g., artificial heart valves or joints) or intravascular lines (e.g., catheters, cerebrospinal fluid shunts). Propionibacteria are also commonly isolated in blood cultures, but this finding usually represents contamination with bacteria on the skin at the phlebotomy site.Acne is unrelated to the effectiveness of skin cleansing because the lesion develops within the sebaceous follicles. For this reason, acne is managed primarily through the topical application of benzoyl peroxide and antibiotics. Antibiotics such as erythromycin and clindamycin have proved effective for treatment.

Mobiluncus

Members of the genus Mobiluncus are obligate anaerobic, gram-variable or gram-negative, curved rods with tapered ends. Despite their appearance in Gram-stained specimens they are classified as gram-positive rods because they have a gram-positive cell wall, lack endotoxin, and Are susceptible to vancomycin, clindamycin, erythromycin, and ampicillin but resistant to colistin.

The organisms are fastidious, growing slowly even on enriched media supplemented with rabbit or horse serum. Two species, Mobiluncus curtisii and Mobiluncus mulieris, have been identified in humans. The organisms colonize the genital tract in low numbers but are abundant in women with bacterial vaginosis (vaginitis).

Lactobacillus

Lactobacillus species are facultatively anaerobic or strictly anaerobic rods.They are found as part of the normal flora of the mouth, stomach, intestines, and genitourinary tract. The organisms are most commonly isolated in urine specimens and blood cultures. Because lactobacilli are the most common organism in the urethraThe reason lactobacilli rarely cause infections of the urinary tract is their inability to grow in urine. Invasion into blood occurs in one of the following three settings: (1) transient bacteremia from a genitourinary source (e.g., after childbirth or a gynecologic procedure), (2) endocarditis, and (3) opportunistic septicemia in an immunocompromised patient.

Treatment of endocarditis and opportunistic infections is difficult because lactobacilli are resistant to vancomycin (an antibiotic commonly active against gram-positive bacteria) and are inhibited but not killed by other antibiotics. A combination of penicillin with an aminoglycoside is required for bactericidal activity.

Lactobacillus

Bifidobacterium and Eubacterium Bifidobacterium and Eubacterium species are commonly found in the oropharynx, large intestine, and vagina. These bacteria can be isolated in clinical specimens but have a very low virulence potential and usually represent clinically insignificant contaminants.

Anaerobic Gram-Negative Bacteria

The most important gram-negative anaerobes that colonize the human upper respiratory, gastrointestinal, and genitourinary tracts are the rods in the genera Bacteroides, Fusobacterium, Porphyromonas, and Prevotella and the cocci in the genus VeillonellaAmong these pathogens, the most important is Bacteroides fragilis, the prototypical endogenous anaerobic pathogen.

Table . Virulence Factors in Anaerobic Gram-Negative Rods

Virulence FactorBacteriaAdhesinsCapsuleBacteroides fragilis, Prevotella melaninogenicaFimbriaeB. fragilis, Porphyromonas gingivalisHemagglutininP. gingivalisLectinFusobacterium nucleatumResistant to Oxygen ToxicitySuperoxide dismutaseMany speciesCatalaseMany speciesAntiphagocyticCapsuleB. fragilis, P. melaninogenicaImmunoglobulin (Ig)A, IgM, IgG proteasesPorphyromonas spp., Prevotella spp.LipopolysaccharideFusobacterium spSuccinic acidMany species

Tissue DestructionPhospholipase CFusobacterium necrophorumHemolysinsMany speciesProteasesMany speciesCollagenaseMany speciesFibrinolysinMany speciesNeuraminidaseMany speciesHeparinaseMany speciesChondroitin sulfataseMany speciesGlucuronidasesMany speciesN-AcetylglucosaminidaseMany speciesVolatile fatty acidsMany speciesToxinEnterotoxigenic toxinB. fragilis Modified from Duerden B: Clin Infect Dis 18(suppl 4):S253-S259, 1994; and Lorber B: Bacteroides, Prevotella, Porphyromonas, and Fusobacterium species. In Mandell, Douglas and Bennett's principles and practice of infectious diseases, ed 6, New York, 2005, Churchill Livingstone.

Virulence FactorBacteria

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