المحاضرة_الثانية_عشر_البكتريا_الطبية_.pdf
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Chlamydia ⊛ Order: chlamydiales. ^è‚éÚøÓÖ]VgéiÖ] ⊛ Family chlamydiaceae. ^è‚éÚøÓÖ]...
Chlamydia ⊛ Order: chlamydiales. ^è‚éÚøÓÖ]VgéiÖ] ⊛ Family chlamydiaceae. ^è‚éÚøÓÖ]íñ^ ⊛ Obligate intracellular bacteria (like viruses). Dl^‰æËÖ]ØnÚE^èø¤]Ø}]^èjÓfÖ]]ˆÖc ⊛ Require biochemical resources of eukaryo>c host cells to fuel their metabolism for growth and replica>on. çÛßÖ]Øq_àÚ^ãeí‘^¤]êñ]„ÇÖ]ØénÛjÖ]íéÛÂíè„ÇjÖì]çßÖ]íéÏéÏuíËé–]^èø~Öíèçéuíéñ^éÛéÒ…]çÚgji J†m^ÓjÖ]æ ⊛ Chlamydia spp. Are similar to gram-nega5ve bacilli in that they have lipopolysaccharide (LPS) as a component of the cell wall. The chlamydial lps, however, has liBle endotoxic ac5vity. Jíé¤]…]‚ql^çÓÚ‚u^Òâ‚Ö]‚è…^ÓÖ]‚è‚ÂîÂëçj^ã]oéu]†¢]ífÖ^‰l^é’ÃÖ]äfi^è‚éÚøÓÖ]íòÊ JØéÎê}]ê^iÔj^ã^Ê ÔÖƒÄÚæz^è‚éÚøÓÖâ‚Ö]‚è†ÓÖ]‚è‚ 1 íè…]‡æíò‰_ Regarding to Chlamydia all the following are true except: ⓐ Facula>ve intracelluar bacteria. ⓑ Requires biochemical resources of eukaryo>c host cells to fuel their metabolism for growth and replica>on. ⓒ The clamydial LPS, however, has liHle endotoxic ac>vity. ⓓ Chlamydiae have a unique developmental life cycle. ⓔ Similar to gram-nega>ve bacilli. ⊛ They have a major outer membrane protein (MOMP) that is very diverse. Jíè^ÇÖÅçßj]êéñ†Ö]êq…^¤]^ÇÖ]°iæ†eÜãè‚Ö ⊛ Chlamydiae have a unique developmental life cycle, * An intracellular, replica>ve form, the re>culate body (RB). * An extracellular, metabolically inert, infec>ve form, the elementary body (EB). H^ãÂçàÚì‚è†ÊíèçÛßiì^éuì…æ‚e^è‚éÚøÓÖ]ÄjÛji JêÓfÖ]Ü¢]H^èø¤]Ø}]…†ÓjÚØÓ* JêÖæù]Ü¢]H^é⁄–è_ØÚ^}Híé¤]t…^}ë‚ÃÚØÓ 2 ⊛ The EB cannot live long periods of >me outside of a host cell. The EB transforms into an RB aPer infec>ng a host cell. ‚ÃeêÖæ÷]Ü¢]±]ÙçvjèÙçvjèêÓfÖ]Ü¢]JíËé–]íé¤]t…^}íèçl]ËÖéÃÖ]^ãßÓµ÷êÓfÖ]Ü¢] JíËé–j]íé¤]íe^‘] ⊛ Within vacuoles, the RB divides via binary fission. The vacuole enlarges and becomes an intracytoplasmic inclusion as the number of RB rises. ‚Â]‡^ÛÒ‡øeçjè^Ö]Ø}]xf’iæĉçjiìçrËÖ]ˆéñ^ßnÖ]…^÷]í‰]çeÜÏßèêÖæ÷]Ü¢]zl]çrËÖ]Ø}] JíéÖæ÷]^q÷] ⊛ The RB then transform back into EB, which are then discharged from the host cell 48 to 72 hours aPer infec>on. There is evidence that, in addi>on to the replica>ve cycle associated with acute chlamydial infec>ons, Chlamydia can persist in vitro in an abnormal form. 72±c48‚ÃeíËé–]íé¤]àÚäq]†}cÔÖƒ‚ÃeÜjèë„Ö]æHêÖæù]Ü¢]±cï†}_ì†ÚêÓfÖ]Ü¢]ÙçvjèÜm á_àÓµHì^£]ì†m‚j]l^e^ãjÖ^eífi†]íè†m^ÓjÖ]ì…æ‚Ö]±cíÊ^ ^eHä_îÂíÖ_Õ^ßâJíe^‘]àÚíÂ^‰ JêÃéfÆØÓej~]»^è‚éÚøÓÖ]†Ûji أﺳﺌﻠﺔ وزارﻳﺔ Chlamydiae occur in: ⓐ Elementary bodies. ⓑ Re>cular bodies. ⓒ complex structure. ⓓ A and B. ⓔ A and C 3 Differential Characteristics Among Chlamydiae That Cause Human Disease اﻟﺨﺼﺎﺋﺺ اﻟﺘﻔﺎﺿﻠﻴﺔ ﺑﻴﻦ اﻟﻜﻼﻣﻴﺪﻳﺎ اﻟﻤﺴﺒﺒﺔ ﻟﻸﻣﺮاض اﻟﺒﺸﺮﻳﺔ Property Chlamydia trachoma>s Chlamydia psiHaci Chlamydia íË’Ö] íè†n£]^è‚éÚøÓÖ] íéñ^ÇffÖ] ^è‚éÚøÓÖ] pneumoniae íèçñ†Ö]^è‚éÚøÓÖ] Host range Humans (expect one Brids, lower Humans †fÖ] Ìé–]íÂçÛ¥ biovar that causes mammals, humans mouse pneumoni>s) (rare) l^éè‚nÖ]H…çéÖ] ëçéuØÚ^ÂçqæÄÎçjE†fÖ] D…^E†fÖ]HíéËÖ] »^è⁄çñ…^e⁄^ãjÖ]gfè‚u]æ Dá]†òËÖ] Elementary body Round Round Pear-shaped morphology ë†ñ] ë†ñ] ï†nÛÒØÓî êÖæ÷]Ü¢]ØÓ Inclusion Round, vacuolar Variable, dense Round, dense morphology íéÆ]†ÊHì†è‚jÚ ÌénÒæÇjÚ íËénÒæì†è‚jÚ °Û–jÖ]ØÓ Glycogen- Yes Üà No ÷ No ÷ containing inclusions îÂëçjÖ]t]…÷] °qçÓé¢] Plasmid DNA Yes Üà Yes Üà No ÷ ë‚éÚ‡øfÖ]ëæçßÖ]˜Û£] Suscep>bility to Yes Üà No ÷ No ÷ sulfonamides l]‚éÚ^çËÖíée^ÏÖ] 4 ‘ Chlamydia trachomatis اﻟﻜﻼﻣﻴﺪﻳﺎ اﻟﺤﺜﺮﻳﺔ ⓐ General Characteristics اﻟﺨﺼﺎﺋﺺ اﻟﻌﺎﻣﺔ ⊛ C. trachoma>s infects humans almost exclusively and is responsible for various clinical syndromes. Jíè†è†Ö]l^Ú‡øj]àÚ‚è‚ÃÖ]àÂíÖæöÚêâæ높uäfØÓe†fÖ]íè†n£]^è‚éÚøÓÖ]gé’i ⊛ Based on major outer membrane protein (MOMP) an>genic differences, C. trachoma>s is divided into 18 different serovars that are associated with different primary clinical syndromes. ^Ë j§ ^’Ú 18 ±c íè†n£] ^è‚éÚøÓÖ] ÜÏßi Hêq…^¤] ^ÇÖ] °iæ†e l]‚–jÚ » íééñ†Ö] l^Êøj}÷] î ⁄ ^ße JíËj§íéÖæ_íè†è†‰l^Ú‡øjfi†i ⓑ Spectrum of Disease ﻃﻴﻒ اﻟﻤﺮض ⊛ Trachoma is manifested by a chronic inflamma>on of the conjunc>va and remains a major cause of preventable blindness worldwide. J^ÃÖ]^©_Ä鶻äßÚíè^ÎçÖ]àÓµë„Ö]îÛÃÖ^é⁄éñ…^f⁄f‰Ø¿iæíÛvj]»àÚˆÚh^ãjÖ]»^Úç}]Ö]îrji ⊛ Lymphogranuloma venereum (LGV) is a sexually transmiHed disease. Jêߢ]Ù^’i÷]è†àÂØÏjßè†Úçâ^é⁄ßqÙçÏß]êËÛÖ]éf£]…çÖ] 5 ⊛ Oculo-genital Infec>ons C. trachoma>s can cause acute inclusion conjunc>vi>s in adults and newborns. The organism is acquired when contaminated genital secre>ons get into the eyes via fingers or during passage of the neonate through the birth canal. ênè‚u Ù^Ëù]æ °ÇÖ^fÖ] ‚ß ^£] íÛvj] h^ãjÖ] íè†n£] ^è‚éÚøÓÖ] íé‰^ßjÖ] íéßéÃÖ] ïæ‚ÃÖ] gfi á_ àÓµ ‚éÖçÖ]…æ†Ú^ßm_æ_Äe^‘ù]è†à°ÃÖ]±címç]íé‰^ßjÖ]l]‡]†Ê]Ø}‚i^Ú‚ßÂê£]àñ^ÓÖ]h^jÒ]ÜjèJì÷çÖ] Jì÷çÖ]ì^ßΠ⊛ Perinatal Infec>ons Approximately one fourth to one half of infants born to females infected with C. trachoma>s develop inclusion conjunc>vi>s. Usually, the incuba>on period is 5 to 12 days aPer birth, but it may be as long as 6 weeks. íè†n£] ^è‚éÚøÓÖ^e l^e^’Ú p^ áæ‚Öçè àè„Ö] Ù^Ëù] Ì’ ±c Äe… àÚ h†Ïè ^Ú ì÷çÖ^e íé] ìËÖ] l^e^ãjÖ] 6±cØ’i‚Î^ãßÓÖæHì÷çÖ]‚Ãe^Ú⁄çè12±c5àÚí^–£]ìÊáçÓi^Úì ^ÂJêÖ^Ûj÷]íÛvj]h^ãjÖ^eáçe^’è JÄée^‰_ أﺳﺌﻠﺔ وزارﻳﺔ Trachoma is manifested by a chronic inflamma>on of the conjunc>va and remains a major cause of preventable blindness worldwide caused by: ⓐ vibrio cholerae. ⓑ H. pylori. ⓒ Chlamydial trachoma>s. ⓓ H. influenzae. ⓔ Brodetella pertussis. 6 Laboratory Diagnosis اﻟﺘﺸﺨﻴﺺ اﻟﻤﺨﺘﺒﺮي ⓐ Indirect method (Culture) (اﻟﻄﺮﻳﻘﺔ ﻏﻴﺮ اﻟﻤﺒﺎﺷﺮة )اﻟﺰرع ⊛ Several different cell lines have been used to isolate C. trachoma>s in cell culture, including McCoy, HeLa, and monkey kidney cells; cycloheximide-treated McCoy cells are commonly used. ^èø}æøéâæëçÓÚ^èø}ÔÖƒ»^H^èø¤]íÂ]…‡»íè†n£]^è‚éÚøÓÖ]ÙˆÃÖíËj§^èø}ç}ì‚Â]‚~j‰] J‚éÛéÓéâçÓéeí¢^Ã]ëçÓÚ^èø}]‚~j‰]ÄéèæW†ÏÖ]îÓÖ] ⊛ APer shaking the clinical specimens with 5-mm glass beads, centrifuga>on of the specimen onto the cell monolayer (usually growing on a coverslip in the boHom of a vial, commonly called a “shell vial”) facilitates adherence of elementary bodies. çÛßi^Úì^ÂEíé~Öíè^uù]íÏfÖ]îÂíßéÃÖëˆÒ†]†Ö]ádÊHÜÚ5Œ^ÏÚêq^q‡‡†íè†è†Ö]l^ßéÃÖ]ˆâ‚Ãe JíéÖæù]^qù]Ñ^’jÖ]ØãèD>íÊ‚’Ö]ì…æ…^Î>ì^ÂîÛiÖ]æHì…æ…^ÏÖ]àÚêËÖ]ˆ¢]»ì†i^‰î ⊛ APer 48 to 72 hours of incuba>on, monolayers are stained with a fluorescein labeled monoclonal an>body. J°‰…çËÖ]íÚøÂØÛ¬íéßÖ]‚éuæ^–ÚÜœíè^uù]l^ÏfÖ]Èf‘ÜjèHí^–£]àÚíÂ^‰72±c48‚Ãe 7 ⓑ Direct Detection Methods ﻃﺮق اﻟﻜﺸﻒ اﻟﻤﺒﺎﺷﺮ 1) Cytologic Examination اﻟﻔﺤﺺ اﻟﺨﻠﻮي ⊛ Cytologic examina>on of cell scrapings from the conjunc>va of newborns or persons with ocular trachoma can be used to detect C. trachoma>s inclusions, usually aPer Giemsa staining. ^Úç}]Ö^e°e^’]”^~ù]æ_ì÷çÖ]ênè‚uÙ^Ëù]‚ßÂíÛvj]àÚ^èø¤]l^ÓÖëç¤]“vËÖ]]‚~j‰]àÓµ.]ˆÛéqÈf‘‚Ãeì^ÂHíè†n£]^è‚éÚøÓÖ]gñ]çàÂÌÓÖíéßéÃÖ] 2) Antigen Detection and Nucleic Acid Hybridization. Jﻛﺸﻒ ﻋﻦ اﻟﻤﺴﺘﻀﺪ وﺗﮫﺠﻴﻦ اﻟﺤﻤﺾ اﻟﻨﻮوي ⊛ To circumvent the shortcomings of cell culture, an>gen detec>on methods are commercially available. J⁄^è…^Ÿ‚–j]àÂÌÓÖ]ц†ÊçjiH^èø¤]íÂ]…‡»…ç’ÏÖ]äqæ_îÂØè^vjÖ 8 ﺔ,+*أﺳﺌﻠﺔ ﺗﺪر What is a characteris>c feature of Chlamydia spp.? ⓐ Gram-positive cell wall. ⓑ Obligate intercellular bacteria. ⓒ presence of peptidoglycan in the cell wall. ⓓ Lack of lipopolysaccharide (LPS). What is a unique about the lipopolysaccharide (LPS) of Chlamydia spp.? ⓐ High endotoxic activity. ⓑ Gram-positive composition ⓒ Absence of LPS. ⓓ Low endotoxic activity. How does the RB divide within vacuoles during the Chlamydia life cycle? ⓐ Mitosis. ⓑ Binary fission. ⓒ Meiosis. ⓓ Budding. 9 When are the elementary bodies (EB) discharged from the host cell during Chlamydia infection ? ⓐ Immediately after infection. ⓑ 24 hours after infection. ⓒ 48 to 72 hours after infection. ⓓ 96 hours after infection. What is the incuba>on period for inclusion conjun>vi>s in newborns born to females infected with C. trachoma>s? ⓐ 1 to 3 days. ⓑ 5 to 12 days. ⓒ 2 to 4 months. ⓓ 6 to 8 months. Which cell lines are the commonly used for the culture of C. trachoma>s in the laboratory? ⓐ Vero cells. ⓑ HeLa cells. ⓒ A549 cells. ⓓ All of the above. 10
