The case study presents an 11-year-old patient diagnosed with a urinary tract infection (UTI) caused by Proteus mirabilis, linked to phimosis. The microbiological evaluation included urine culture, biochemical testing, and antibiotic sensitivity assessment. The findings revealed significant bacteriuria and offered insights into treatment options and the organism's pathogenic characteristics.

1. CLINICAL CASE PRESENTATION
MICROBIOLOGYASSIGNMENT
ARPITA CHANDRA

2. PATIENT ID
ADMISSION DATE- 07/11/22
AGE/GENDER - 11/M
WARD- SURG-I
REG NO- 1677980
PATHO NO.- 88
SAMPLE- URINE

3. HISTORY OF PATIENT
Chief complaints- Urinary hesitation, Fever, Burning
micturation, Incomplete voiding of urine
Diagnosis- Phimosis
Treatment- Not on any antibiotics
General condition- Not well,
Going for surgery (OT)- Circumcision
Microbiological Diagnosis- Proteus mirabilis organism
isolated (09/11/22)

4. URINE SPECIMEN
COLLECTION
1. Midstream urine (for culture and AST )
Sterile Wide mouthed container
Before collection
Genitalia should be properly cleaned
With soap & water
Then
Mid portion of the stream is collected

5. 2. CATHETER SPECIMEN
Collect directly from catheter tube not from catheter bag.
3. From infants
Suprapubic Aspiration
TRANSPORT
Process with minimum delay
If not possible – Refrigerated at 40°C or stored by adding
boric Acid.

6. PHYSICAL EXAMINATION
- COLOUR
- VOLUME
- ODOR
- SPECIFIC GRAVITY
- PRESENCE OF BLOOD

7. After Centrifugation of urine sample
Supernatant Sediment
Chemical analysis
1. pH
2. Glucose
3. Protein
4. Ketone bodies
5. Urobilinogen
6. Bilirubin
7. Nitrite
8. Bile salts, Bile pigments
9. Blood
Wet mount preparation
(examined under 40X)
1. Pus cells
2. Crystals
3. Microorganism
4. Parasites
5. BYC
6. RBCs

9. CULTURE FROM SEDIMENT PART
STREAK ON
CLED (Primarily used for urinary pathogens)
Also Can be used
 Nutrient agar
 Blood agar
 Mac-Conkey

10. (After 24 hrs of incubation at 37°C Observe Colony Morphology From
Culture plate (CLED Agar)
( Non Lactose Fermenting, Translucent Blue colour colonies )

11. COLONY COUNT BY KASS TECHNIQUE (1956)
Total Bacterial count per ml = Number of colonies x 200
Number of colonies = No. of Bacteria present
INTERPRETATION OF RESULT
1. >105 Bacteria/ml = Significant Bacteriuria (Active UTI)
2. Between 104 to 105 Bacteria/ml = doubtful Significance
(Repeated culture)
3. <104 Bacteria/ml = No significance growth
(more than 3 type= regarded as contamination)

12. Marked isolated colonies for smear
Smear preparation & Gram stain
Examine under oil immersion (100X)
GNB (Coccobacilli)
Catalase (+ve) Oxidase (-ve)
Enterobacteriaceae

13. Hanging drop
Motile
Non lactose fermenting (Suspected)
1. Salmonella
2. Proteus
GNB process with All biochemical and AST

14. AFTER 24 HRS OF INCUBATION ( OBSERVE ALL
BIOCHEMICALS AND AST)
PUS CELLS- 8-10/hpf
Indole- Negative COLONY COUNT > 105 CFU/ML
Citrate- Positive
Urease- Positive
TSI- K/A with H2S gas
Manitol- Non motile Non ferment
Urease (+) TSI(K/A with H2S) Citrate(+) Indole (-)

15. ANTIBIOTIC SENSITIVITY TEST
Sensitive to- PI, CPT,AMP, CTX, A/S, CX, IPM, CPM, CIP, NET, MRP,
CFS, TOB, LE, GEN, AT, PIT, OF, TCC
Resitance to- TGC, NIT, PB, CL
Inrinsic Resistance to- Tetracycline/ Tigecycline, Nitrophuran, Polymixin,
colistin ( There is no intrinsic resistance to penicillin and cephalosporin in
this organism)
Organism Isolated- Proteus mirabilis

16. DEFINITIVE DIAGNOSIS
Patient having UTI and the causative agent is Proteus mirabilis
Cause of UTI
Patient having Phimosis – Tight foreskin can’t be pulled back over the
head of the penis
In this condition patient is unable to
completely empty their bladder and
the stagnant urine acts as a growth
medium for bacteria
Having Symptoms- Fever,
Urinary hesitation
Burning micturation

17. PROTEUS MIRABILIS
Family- Enterobacteriaceae
Genus- Proteus
Species- Mirabilis
Morphology-
Pleomorphism
Gram negative coccobacilli
Non capsulated
Non sporing
Peritrichous flagella
Fimbriae present
Antigenic property-
‘H’Ag (Flagellar Ag)
‘O’Ag (Somatic Ag)

18. PATHOGENESIS
Saprophytes- isolated from decomposing animal matter, sewage and soil
Commensals- Moist area of the skin intestine of humans
Infections-
1. Opportunistic pathogen
2. Urine
3. Wound
4. Soft tissue infections
5. Septicemia
Struvite stones in bladder- Proteus produces urease which converts urea into
ammonia which damage renal epithelium makes urine alkaline and start
deposition of phosphate – formation of Renal Calculi

19. LAB DIAGNOSIS
Pleomorphism- Gram negative coccobacilli
Odor- putrid fishy or seminal odor in culture
Swarming- Ability to swarm
Biochemical reactions
Indole- negative
Urease- positive
Citrate- positive
TSI- K/A with gas H2S Gas
Ornithine ddecarboxylase test- positive

20. SWARMING MOTILITY OF PROTEUS MIRABILIS

21. CULTURE
Aerobic and faculatative anaerobic
Motility seen on Blood agar and Nutrient agar
Motility not seen in Mac conkey agar and cled agar

22. On Mac conkey Agar- Non lactose fermenter
On Blood agar showing swarming motility

23. TYPING OF PROTEUS
1. Bacteriocin typing
2. Bacteriophage typing
3. Ribotyping
4. Dienes phenomenon- When 2 strains of Proteus inoculated at different
area on a culture plate
- If swarming of 2 strain merge incompletely = separated by narrow line
= indicates 2 strans are different
- If swarming of 2 strains merge completely without any line of
demarcation = indicate 2 strains are identical

24. TREATMENT
Slow intrinsic resistance to
- Nitofuratoin tetracycline and polymixin colistin
-They produces ESBL and AMP Beta lacatamase
-Effective Treatment- Aminoglycosides and Qinolones

26. AFTER INCUBATION OF 24 HR’S AT 35°C
Observe colony morphology from culture plates
Marked isolated colonies for smear
Smear preparation and gram stain
(examined under oil immersion-100X)
GPC GNB
Gram positive cocci Gram Negative bacilli