Presentation collection from Seminar on Infections of the compromised host seminar. Compromised host state leads to many illnesses. This is a outline of these conditions.

1. Infections of the compromised
host
Year 3 Semester 2
2007/08 Batch
Faculty of Medicine
University of Peradeniya
Sri Lanka

3. Following topics will be discussed.
1. Chronic diarrhoea in post transplanted patient
2. Haemorrhagic Chicken Pox
3. Sepsis in a baby born to a mother with PROM
4. HIV/Leishmaniasis co-infection
5. HIV-AIDS associated opportunistic infections of the
respiratory system
6. Post oesophagectomy patient developing fever on 3rd
day post operative in ICU
7. A patient with a history of mitral valve replacement
developing fever after 7 months of surgery.
8. A paraplegic patient on long term indwelling catheter
9. Non healing foot ulcer in diabetic patient

4. 1. Chronic diarrhoea in post transplanted patient
Causative agents
•Bacterial-Mycobacterium avium-
intercellulare complex
•Viral- CMV
•Parasitic-Cryptosporidium spp, Isospora
belli,
Microsporidium, Strongyloides
stercoralis
Immunosuppressive drugs
1. Suppress cell mediated immunity
2. Suppress humoral immunity

5. 1st option-reduce
Management immunosuppressive drug regimen
Causative agent Diagnosis Treatment Prevention
M.Avium- Blood culture Clarithromycin+ Prevent aerosol
Intracellulare (ethambutol,rifabutin,cipr tranmission
ofloxacin)
CMV Culture, PCR Gancyclovir, foscarnet (reactivation)
Cryptosporidim Stool concentration/ Modified Paromamycin, Safe food and water,
spp. acid fast stain for oocysts Nitosoxanide, hygiene
Immunofluorescence assay Azithromycin (not
practiced in SL)
Isospora belli Wet smear/ Albendazole, Safe food and water,
Modified acid fast stain for Mebendazole hygiene
oocysts
Microsporidium stain the fecal sample with Albendazole, Safe food and water,
modified trichrome stain to Mebendazole hygiene
detect spores ,Electron
microscopy,immunoflurescenc
e assay
Strongyloides Rabditiform larva detection in Ivermectin, Albendazole Proper sewage disposal,
stercoralis stools foot wear

6. 2.Haemorrhagic Chicken Pox
 Aetiology - Varicella zoster virus
 Potentially fatal disease
 Affects immunocompromised individuals
 Adults and children with
deficient cellular immunity
 Leukemia, steroid therapy
and AIDS

7. Five major clinical syndromes
 Febrile purpura
 Malignant chicken pox
 Post infectious purpura
 Purpura fulminalis
 Anaphylactoid purpura
Diagnosis
 Tzanck smear - Cellular changes and EM
 Ag detection (Fluorescent antibody test)
 Culture and Ag detection
 DNA - PCR
Management
 Acyclovir treatment
 Adequate wound care
 Prevention

8. Antimicrobial
properties of
amniotic fluid
Intact foetal
membranes
Closed internl
Thickened os
mucus
plug GBS,E coli, Listeria

9. DIAGNOSIS
 Neonatal :- Blood culture , ESR / CRP , FBC
 CSF examination
 Maternal :- Vaginal swab, Amniotic fluid, Blood culture
MANAGEMENT
• Supportive therapy
• Antibiotics

10. Breached defenses Reasons for breach
• Innate immunity- breach • IV Drug abuse
in the skin • Blood transfusion
• Adaptive immunity- • Sexual transmission ?
breach in CMI
4.HIV/Leishmaniasis co-infection
Mechanism of breach
HIV Leishmaniasis
•
• CD4+ T cell loss T cell depletion
n
Co - infection
• Further reduction in T cell count
• Increase viral replication by parasites
AIDS

11. • ELISA for Anti HIV Ab For HIV
• Western blot (serum)
Diagnosis • PCR – Viral RNA
• Microscopy (blood & BM) For
Leishmaniasis
• Immunochromotographic test
• Anti-leishmanial drugs: Amphotericin B
Na antimony
Management oral Miltefosine
• HIV drugs : HAART
• Prevention of IV drug abuse
Prevention • Safe blood transfusion
• Control of parasites

12. 5.HIV-AIDS associated opportunistic
infections of the respiratory system.
Infectious Diseases
 Bacterial pneumonia,Pneumocystis jiroveci pneumonia,Other
fungal pneumonia,Mycobacterium tuberculosis
 need for prompt treatment.
History & Examination
 geographic location BACTERIAL
MYCOBACTERI
FUNGAL
VIRAL/
AL PARASITC
Immunology Pneumocystis
Streptococcus Mycobacterium Cytomegalovir
 CD4+ cell count pneumoniae tuberculosis jirovecii s
Haemophilus Mycobacterium
Laboratory Tests species kansasii
 White blood cell count, Pseudomonas Mycobacterium Histoplasma
Serum lactate dehydrogenase,aeruginosa avium complex capsulatum
Arterial blood gas Staphylococcus Coccidioides
aureus immitis
Chest Radiograph/CT/MRI Aspergillus
Klebsiella species
Bronchoscopy pneumoniae
(esp. fumigatus

13. Serology or
Pulmonary Pleural Important
Blood Sputum BAL
Disease Fluid Other Sites
Cultures
 HIV-associated neoplasms or other disorders.
 Finally, HIV-infected persons may have preexisting pulmonary
disease (e.g., asthma),
 pulmonary disease unrelated to their HIV infection (e.g., pulmonary
embolism) may develop and be the cause of their symptoms.

14. 6.Post oesophagectomy patient developing
fever on 3rd day post operative in ICU
Common Breech of
organisms defence
Gram –ve Breech of Common
•Mucociliar
bacilli y
defence organisms
Gram +ve escalator,
cocci •reflux Normal skin flora
closure of
S. aureus glottis ET tube/ CVP •Coagulase -ve
Fungi •CMI & HI ventilator line skin staphylococcus
Viral s •Candida
Cannula •S. aureus
•E.coli including MRSA
•Candida
spp. • damage
•Klebsiella to mucosa, Normal skin
•Pseudomon •Flushing flora
as spp.
mechanis
Urinary Surgica •S. Aureus
m
•Enterobacter •Direct cathete l skin •C. Diphtheriae
spp. access to r incision •Candida
•Citerobacter
bladder
site •Cryptococcus
•Proteus Gut flora
•anerobes

15. Specimens Management
1. Hx & clinical examination
1. Blood for culture and ABST
2. Urine for culture and ABST 2. Fever chart maintanance
3. CVP line tip culture 3. Investigate for aetiological
4. Sputum –if difficult to agents & manage accordingly.
obtain,transtrachial aspirate
& bronchoscopic biopsy Wound infection – proper wound
5. Incision site pus for culture cleaning & proper antibiotics
6. Drain fluid UTI - remove catheter
do not catheterised unless
essential
aseptic procedures
Prevention antibiotic only on evidence of
1. Aseptic surgical procedures infection
2. Minimise drains,catheters & Respiratory tract infection
IV lines post operatively Proper antibiotic usage and
3. Avoid pre-operative chest
antibiotics, physiotherapy
4. Give peri operative AB s CVP line and Cannula site
5. Minimize pre-op
infection
hospitalization
6. Eliminate nasal colonization
of S. Aureus

16. 7.A patient with a history of mitral valve replacement
developing fever after 7 months of surgery.
Breached defenses Bacteremia.
•Absence of blood •Poor dental hygiene?
supply. WITH •IV drug use?
•Abnormal blood flow. •Soft tissue infection?
•Occult source?
Suspicious case of Prosthetic Valve
Endocarditis
Early (< than 60 days)
• Staph aureus, Staph epidermidis
Bacterial
endocarditis Late(>than 60 days)
• Strep viridans 50%-70% (Streptococcus
sanguis,
Strep.oralis Strep.
mitis)
Rare causes: HACEK Group & Culture negative BE
• Staph aureus 25%

17. Diagnosis ?
History
Examination > Splinter hemorrhages, Janeway lesions, Osler’s node, Roth
spots.
Investigations >Blood culture, FBC, ESR, CRP, Liver biochemistry, ECG,
Echocardiography
Blood culture
•Blood samples should be taken prior to antibiotic use.
•At least 3 sets of samples ( 6 bottles)
•Under aseptic condition.
•Do NOT use cannula
Management
• Start empirical antibiotic treatment
• Change or continue antibiotics according to the patient’s response
and culture results.
• Decision about surgical intervention should be made after joint
consultation between cardiologist and cardiothoracic surgeon.
Prevention
•Use prophylactic antibiotics prior to dental & surgical procedures.
•Good dental hygiene.
•Avoid risky behaviors such as i.v. drug abuse.

18. Case Summary: Mrs. X, year old paraplegic for
months on indwelling catheter presented with fever for
day with chills and burning sensation in urethra.Past
medical history, DM for yrs
 Symptoms and signs:
Fever, Chills, Burning sensation of
Urethra & Pubic
area, Nausea, Headache, Mild lower
back pain
 Problems Catheter
Immunocompromised
Paraplegic and its complications
Female
Old age

19. Diagnosis - Catheter associated complicated UTI
COMMON ORGANISMS…
MECHANISMS OF UTI… # E.coli
• Mechanical trauma to urethra # Klebsiella
• Introducing normal flora # Proteus & Candida
• Bladder atonia - VU valve
incompetence PREVENTION AND
•Diabetis: reduse immunity MANAGEMENT…
• Urine retention
• Ascending infections Management…
Predisposing factors
COLLECTION , STORAGE & Antibiotics
TRANSPORTATION OF URINE
SPECIMEN FOR LAB Prevention…
INVESTIGATIONS… Avoid catheterisation
Minimum duration
# UFR Intermittent catheterisation
# Urine culture Aseptic conditions
# FBC Closed, sterile drainage
# Blood culture system
# ABST Maintain gravity drainage
Prophylactic antibiotics

20. NON HEALING FOOT ULCER IN DIABETIC PATIENT
Pathophysiology
Defense How it is compromised
Skin Trauma
Reflexes(pain) Loss of sensation due to diabetic neuropathy
Repair mechanisms Reduce blood supply by diabetic vasculopathy
Immunity Alteration of cellular and humoral immunity
Coordination Poor coordination due to reduced sensation ,poor vison
ect.
Organisms involved
Polymicrobial cause- mostly involved
Staphylococcus aureus
group A beta haemolytic Streptococcus
Staphylococcus epidermidis Pseudomonas aeruginosa
gram negative anaerobes Candida spp.
Gram negative aerobes Clostridium perfringens
Enterococcus

21. Assessment of vascular insufficiency-
Bacterial cultures &
Proper Hx & Ex peripheral pulses, Doppler U.S
ABST-
Laboratory testing- DIAGNOSIS
WBC Radiological testing-
count, ESR, glucos plain x-ray
e, etc...
 MANAGEMENT
 Good diabetic control.
 Ulcer Mx - elevation, soft tissue support & antibiotics
with appropriate wound management.
 Ulceration with deep tissue invasion-rest, elevation, antibiotics for
secondary infection & protracted treatment with wound management.
 Mx of vascular insufficiency. ( Medical and Surgical )
 If infection persists & leading to complication -amputation done
 PREVENTION
 Good diabetes control
 Foot care
 Educating the patient.