Most UTIs are caused by facultative anaerobes that are able to grow under either anaerobic or aerobic conditions and usually originate in the bowel flora

Most UTIs are caused by facultative anaerobes that are able to grow under either anaerobic or aerobic conditions and usually originate in the bowel flora. Uropathogens such as S. epidermidis and Candida albicans originate in the flora of the vaginal or perineal skin.

E. coli is by far the most common cause of UTI, accounting for 85% of community-acquired and 50% of hospital-acquired infections. Other gram-negative Enterobacteriaceae including Proteus and Klebsiella, and gram-positive E. faecalis and Staphylococcus saprophyticus are responsible for the remainder of most community-acquired infections (Hooton, 1999). Complicated or nosocomial infections are frequently caused by E. coli and E. faecalis (Hall LM et al, 1992) as well as by Klebsiella, Enterobacter, Citrobacter, Serratia, Pseudomonas aeruginosa, Providencia, and S. epidermidis (Kennedy et al, 1965).

Patients with diabetes are more likely to have urinary tract infections caused by Klebsiella, group B streptococci, Aerococcus and non albicans Candida. Klebsiella and group B streptococcus are two to three times more common in patients with diabetes than in patients without diabetes.

Less common organisms such as Gardnerella vaginalis, Mycoplasma species, and Ureaplasma urealyticum may infect patients with intermittent or indwelling catheters (Josephson et al, 1988).

The prevalence of infecting organisms is influenced by the age of the patient. For example, S. saprophyticus is now recognized as causing approximately 10% of symptomatic lower UTIs in young, sexually active females (Latham et al, 1983), whereas it rarely causes infection in males and elderly individuals. A seasonal variation with a late summer to fall peak has been reported (Hovelius and Mardh, 1984; Hedman and Ringertz, 1991).

Soal TP.

1. jelaskan 4 cara pengambilan contoh urin !

Katerterisasi

Aspirasi kantung kemih

Segmented voided urin spesimen (clean-voided midstream urin)

Urunalisis (kuantitatif urin kultur)

2. jelaskan singkat pemeriksaan bakteriologi terhadap pasien diagnosa UTI(urinary tract infection)?

Kultur urin (quantitative urin kultur)

Tes biokimia

Tes sensitivitas AM

Kreatinin Clareance

Urea dan kesimbangan elektrolit

Kesimbangan asam basa

3. Sebutkan 3 bakteri yang sering menyebabkan ISK(infeksi saluran kemih) serta karakteristiknya ?

Escerichia coli(Gol. Enterobacteriaceae)

Staphylacoocus aureus

Gol. Enterobacteriaceae seperti

Pseudomonas

Proteus

klebsiella

4. sebutkan tes2 biokima u/ identifikasi enterobacteriaceae serta :

Tes2 biokma yang umum u/ bakteri adalah(sherris medical mikrobiologi 4th ed,2004,sampul kuning)

1. pemecahan karbohidrat=kemampuan menghasilkan produk metabolit asam(+)

2. produksi katalase=mampu mengubah hidrogen peroksida menjadi ait dan gas oksigen(-)

3. penggunaan sitrat=mampu memakai [Na-]sitrat sebagai sumber energi(+)

4. koagulase=menghasilkan enzim (apa?) yang mengubah fibrinogen menjadi fibtin clot

5. Dekarboxylase dan deaminases=terhadap Asam amino lisin,ornitin,arginin

6. Hidrogen sulfida=menghasilkan H2S dari asam amino

7. Indol=menguba trytofan ( Indole, sebuah benzopyrrole

8. Nitrat reduction=kurangi produksi nitrat melalui deteksi gas nitrit dan nitrogen

9. O-Nitrophenyl-Beta-D-galactoside (ONPG) breakdown

10. Produksi oksidase=deteksi component C dari kompleks sitokrom-oksidase

11. produksi proteinase=dari medium gekatin atau telur terkoagulasi

12. produksi urease=hidrolisis urea menjadi amonia dan CO2. pH meningkat karena amonia.

13. Voges-proskauer test=deteksi acetylmethylcarbinol(acetoin), metabolit intermediate dari jalut glicol dalam fermentasi glukosa

i. jelaskan prinsip masing2 tes !

ii. sebutkan cara interpretasi hasil masing2 tes !

5. Mengapa medium agar MacConkey digunakan u/ kultur bakteri bakteri penyebab ISK ?

Medium agar MacConkey(MAM) adalah medium yang selektif dan indikator untuk bakteri basil gram (-), pada umumnya family Enterobacteriaceae dan genus Pseudomonas. Disamping peptone base, MAM mengandung bile salt, kristal violet, laktose, dan zat pewarna merah sebagai indikator pH. Bile salt dan kristal violet menghambat pertumbuhan bakteri gram (+) dan memacu pertumbuhan bakteri gram (-), seperti Neisseria dan Pasteurella. Bakteri basil gram (-) bertumbuh dan fermentasi laktose dan menghasilkan koloni asam berwarna merah, dengan perbedaan morfologi koloni.(Sherris medical mikrobiologi 4th ed,2004,sampul kuning)