this is precise descrition about bacterial innfection

1. Infectious disease

2. Shigellosis
• Non motile gram negative rod
• Acute infectious inflammatory colitis due to
shigella spp.
– 4 clinically important spp: S. Dysentriae, S. Flexneri, S.
boydii, S. sonnei
• Transmission Feco-oral route
• Presentation: - Fever, frequent dysentery (10-30 times
per day) of small volume bloody, mucoid and pus
diarrhea accompanied by severe abdominal cramps
and tenusmus (Complicated by rectal prolapse in young
children)

3. Complications
– Toxic mega colon
– Colonic perforation
– Dehydration + electrolyte imbalance
– Protien-losing enteropathy with extensive colonic
involvement  PEM in poorly nourished children
• Bacteremia - More common in infants,
malnourished and
• AIDS patients

4. • DDX: - Other infectious, parasitic and IBD
• Dx: - Stool culture /Rectal swab for culture
– EIA to detect shiga family toxins in stool
• Rx: Oral rehydration solution + electrolyte
replacement
• Antibiotics for severe dysentery:
fluoroquinolones, Ceftraxone, Azithromycin
-Reduce duration of illness
- Shorten the carriage state
• Nutritional support-: High caloric diet

5. Prevention
• No licensed vaccine against shigella
• Environmental hygiene
• Hand washing with water and soap
• Safe water supplies and toilet sanitations

6. Salmonellosis
• Salmonella spp. > 2400 serotypes
• Motile, Non-spore forming Gram-ve bacilli
• Grow in humans and animals
• S.typhi and S.paratyphi are restricted to human
host causing enteric fever

7. Typhoid/ enteric fever
• Ingestion of contaminated food and water
• (inoculum dose 103-106cfu) by susceptible host (Stomach acidy,
Achlorhydric diseases, Antiacid ingestion, Age <1yr, Intestinal
integrity, IBD, GI Surgery, Broad spectrum antibiotic use)
•  Penetration of gut mucosal layer and infection of payer’s
patches (phagocytosed by macrophages)
•  Dissemination throughout the body via lymphatics and
colonize RES  Re infection of intestine as well as other body
parts via hematogenous dissemination.

8. Presentation
• IP 3-21 days
• Step ladder pattern fever (75%) + abdominal pain (20-40%)
• GI symptoms: diarrhea (AIDS patients, Age <1
yr)/constipation
• Rose spots: Maculopapular blanching rash over the trunk
and chest
• Hepatosplenomegaly, Epistaxis
• Relative bradycardia, Delirium/ coma

9. Complications
• Intestinal perforation /bleeding
• hepatic /splenic abscesses
• Meningoencephalitis
• Nephritis, Arthritis /osteomyelitis
Relapse rate despite Rx =10%
Chronic carriers: 1-5 % - asymptomatic individuals who shed
S.typhi in urine or stool for >1yr
High incidence in women, individuals with biliary tract
abnormalities (stone /tumor) and GI malignancy.

10. DIAGNOSIS
• 15-25% of cases → leukopenia and neutropenia; the majority of cases
→ normal WBC count despite high fever .
• Moderately elevated LFT.
• Dxc “gold standard”- a culture positive for S.typhi or S.paratyphi.
– *Blood culture (yield) -1st week:90%, 3rd week:50%
– Bone marrow cultures remain 90% sensitive despite < 5 days
antibiotic therapy .
• PCR and probe assays → being developed Rx

11. – Stool cultures – negative in 1st week in 60 to70%
of cases; can become positive during the third
week in untreated patients.
– 90% of patients clear bacteria from the stool by
the eight week.
• Serology –Widal test – high rates of false
posititivity and false negativity → clinically not
useful.
• PCR and probe assays → being developed

12. TREATMENT
• Current empiric treatment:- Quinolones or 3rd
generation cephalosporins.
• *ceftriaxone 1 to2 gram iv or im for 10 to14
days
• - Quinolones are the only available oral
antibiotics for the treatment of MDR S.typhi:-
ciprofloxacin 500mg po bid for 10days .
• ofloxacin 10-15mg kg in divided doses twice
daily for 2 to 3 days.

13. Non-typhoidal salmonellosis
• S. typhimurium - S. eneritidis
• Highest Morbidity and Mortality among:-
– Elderly/
– Infants,
– HIV infected individuals,
– Patients with hemoglobinopathies,
– Pts with blockade of RES,
– Bartonellosis,
– Malaria,
– Schistosomiasis,
– Histoplasmosis.
• Transmission: contaminated and under cooked food

14. Clinical manifestations
• Gastroenteritis
• Bacteremia
• Localized infections: Intra abdominal infection, Hepatic
/Splenic abscess, Cholecystitis
• Meningitis
• Pneumonia
• UTI:
• Bone/Joint infections

15. Treatment
• GE does not require treatment with antibiotics
usually is self limiting and antibiotics may be
associated with increased risk of carriage.
• Antibiotic tx is indicated for metastatic
infections and immune suppressed patients.

16. Vibrio
• Gram negative curved rod with polar flagella
• Growth on alkaline media
• Spp: vibrio cholerae
– V. parahemolyticus
– V. vulnificus
V. Cholerae
– Reservoir – human colon, invertebrate animal
contaminations (shell fish)

17. Cholera
• Acute diarrheal disease that leads to death with severe
dehydration.
• Occur in epidemics.
• Etiology: - v cholera serogroup 01.
– New serogroup in India 0139;
– no identified animal reservoir
• Transmission: fecal contamination of water and food
• Risk groups:
– achlorhyrdia (use of antiacid or food buffering),
– children,
– blood group O.

18. Pathogenesis
• Cholera toxin mediated increase of cellular cAMP which
• inhibit the villus cell Na+ absorption and
• activates secretary Cl- transport in crypt cells.
• This results in high volume isotonic fluid accumulation in the
lumen beyond the reabsorptive capacity of the intestine and
massive diarrhea > hypovolemia – shock – death

19. Clinical manifestations
• IP – 24 – 48 hours
– Sudden onset painless, voluminous watery diarrhea associated with
vomiting. stool volume may exceed 250ml/Kg.
– No fever
– Stool – non bilious, gray, cloudy, with flecks of mucus, no blood, sweet
non offensive odour – rice water stool.
– Electrolyte disturbances, renal dysfn,
– Lab.
– Hemoconcentration,
– leukocytosis with PNL dominance,
– rise in BUN, Cr;
– normal Na, K, Cl;
– reduced bicarbonate,
– elevated anion gap,
– low arterial pH

20. Diagnosis
• demonstration of v cholera organism in stool eg
wet mount and dark field microscopy
• Culture on thiosulphate-citrate-bile salts-sucrose
agar

21. Treatment
Adequate replacement of fluid and electrolytes
• ORS (Na+ 90mmol/l, K+ 20, Cl- 80, citrate 10, glucose 110)
• Antibiotics: TTc 2gm stat, Doxycycline 300mg stat
• Alternatives: ciprofloxacillin, erythromycin, cotrimexazole
• Prevention – safe water supply and sanitary disposal of
feces
• Vaccines – under development

22. Spirochetal diseases
• Treponematosis – syphilis, pinta, bejel, yaws
• Leptospira – leptospirosis
• Borrelia – relapsing fever, lyme disease

23. Syphilis
• Etiology: Treponema pallidum
• Slender, spiral microaerophilic gram-negative
rods
• Not cultured in artificial media, fertilized eggs
and tissue culture
• Limited metabolic capability

24. Transmission
• Almost always sexual,
– rarely – vertical,
– blood transfusion,
– organ transplantation
• Penetrate intact mucus membrane and micro
abraded skin
• Median IP = 3 weeks (500-1000 organisms for
naturally acquired infections)
• Prevalence decreased after invention of penicillin

25. Clinical features
• Four stages of acquired syphilis
• Tuskegee study conducted between 1932 and 1962 collected data on 431 black men
whose syphilis was untreated

26. Primary syphilis
• Hard chancre: Clean based, non tender, indurated
single genital ulcer with bilateral non tender
inguinal LAP
– Multiple 10 lesions in men with HIV infection
– Atypical 10 lesion is common: depends on inoculums'
dose and host immunity
– E.g. Papules only with small inoculums dose
– Persist for 4-6 weeks and then heals spontaneously

27. Secondary Syphilis
• Constitutional, mucocutaneous and parenchymal
manifestations after 6- 8 wks of 10 lesion healing
• Mucocutaneous lesions with generalized LAP
• Macules, Papules, papulosquamous lesion over the
trunk, proximal extremities, and palm and sole
• Constitutional symptoms (as many as 30%)

28. Secondary syphilis conti …
• Acute meningitis (40% + ve CSF abnormality)
• Persisting /Healing 10 lesions (15%) esp. in HIV infected
pts
• There may be Hepatitis, Nephritis, Arthritis, Periostitis,
Colonic ulcers/masses, Ocular abnormalities (optic
neuritis, uveitis /iritis)
• 10 and 20 syphilis are rich in spirochetes from site of
lesion and patients are highly infectious

29. Latent syphilis
• Patients are symptom free and diagnosis is by
serologic test, but still infectious
– Early latent syphilis - Occurs within 1 yr of
developing 10 syphilis
– Late latent syphilis - Occurs after 1 yr of infection
or unknown duration
• 70% of untreated cases do not develop
clinical late syphilis (late latent and 30 syphilis)
but spontaneous cure is doubtful

30. 30 syphilis
• CNS manifestation of syphilis is continuum of early
invasion or asymptomatic involvement, or early or
late development of neurologic abnormality
1. Asymptomatic neurosyphilis
• Only laboratory abnormalities characterized by
mononuclear pleocytosis (> 5 cells /l) ,  CSF
protein or reactive CSF VDRL
• Up to 40% of 10 and 20 syphilis; and 25% of latent
phase pts are at risk of neurologic complication

31. • T. pallidum isolation can be found in 30% in
CSF without other CSF abnormalities
• Higher risk with  duration of disease, CSF
pleocytosis degree and  CSF protein
concentration

32. Symptomatic neurosyphilis
• Categories Onset of symptoms after
infection
• Meningeal neurosyphilis <1 yr
• Meningovascular syphilis 5-10 yrs
• General Paresis 10-20 yrs
• Tabes dorsalis 25-30 yrs
• Usually present with mixed, subtle or incomplete syndromes

33. Diagnosis
1. Demonstration of the Organism
• Dark-Field microscopy of lesion exudates in 10 syphilis
/condylomata lata (20 syphilis)
• Silver stain /IF staining/Immunohistochemical methods of
tissue
• PCR in research lab.

34. Dark field microscopy

35. 2. Serologic tests for syphilis
• nontreponemal tests:
– Venereal Disease Research Laboratory (VDRL)
– Rapid Plasma Reagin (RPR) test,
– Measure IgG/ Ig M direct against cardio lipin lecitin cholestrol
antigen complex
• Uses:
– For initial screening and diagnostic purposes
– For quantitation of serum Abs
– Titer reflect disease activity (with disease evolution )
– Four fold reduction in Ab titer in adequate Rx response

36. • Treponemal tests:
– fluorescent treponemal antibody absorption (FTA-ABS)
– microhemagglutination test for antibodies to Treponema
pallidum (MHA-TP)
– Treponema pallidum particle agglutination assay (TPPA).
• Uses
– Confirmation of (+ve NTTs) - Disease diagnosis

37. Treatment
1. Early Syphilis - 10/20 syphilis /early latent syphilis
– Benzathine penicillin 2.4 mu im stat
– Alternatives: tetracycline/ Doxycycline
2. Late latent /late syphilis
• Late latent syphilis with normal CSF profile
• Cardiovascular syphilis
• late benign syphilis (Gumma)
– Benzathine penicillin , 2.4 mu im/Week for 3 weeks
• Alternatives : Doxcycline / Tetracycline (100mg , BID /500mg ,QID
for 4 weeks)

38. Treatment of neurosyphilis
• IV penicillin G: 4 mu lV q 4 hrs for 10-14 days
• Alternative : No data proven alternative drug
• for penicillin allergic pts – desensitization and tx with pen.
• ? 3rd generation cephalosporins, - ? Azithromycin
• In HIV pts additional penicillin 1.2 mu IM weekly for three
doses.
• No vaccine so far, no defined immunity after infection.

39. Thanks so much!!!