Opportunistic infection: An infection caused by an organism that does not usually cause
disease in a healthy person with a normal immune system.
• When the immune system is compromised such as through HIV infection, this creates an
‘opportunity’ for the pathogen to infect.
• OIs are important HIV indicator diseases and may be the trigger for an HIV diagnosis
• The natural history of HIV involves a progressive loss of CD4 T lymphocytes
• As CD4 level declines, risk of contracting OIs increases.
• OIs may be bacterial, viral, fungal, or parasitic.
• Any body organs/systems can be affected.
Common Opportunistic Infections
HIV-Related Respiratory Illnesses
• Common OIs affecting the respiratory system include
Bacterial Pneumonia
Pneumocystis jirovecii pneumonia (PCP)
Tuberculosis
• Other OIs affecting the respiratory system include
Atypical bacteria (chlamydia and mycoplasma)
Toxoplasmosis, cytomegalovirus (CMV) and Mycobacterium avium complex
(MAC)
Cryptococcosis
Opportunistic Infections Affecting Central Nervous System (CNS)
• There are many Opportunistic infections that can affect the CNS, the commonest being
Bacterial meningitis
Cryptococcal meningitis
Tuberculous meningitis
Toxoplasmosis
• Other infections that may affect the CNS include
CMV (encephalitis)
HSV (encephalitis)
JC virus (progressive multifocal leukoencephalopathy)
Opportunistic Infections Affecting Gastrointestinal Tract
• Oro-oesophageal diseases
• Candidiasis ‘thrush’
• Herpes simplex virus (HSV)
• Aphthous ulcers
• CMV ulcers
• Kaposi sarcoma
• Diarrhoeal illness
OIs Affecting Skin
• Viral infections such as herpes zoster, Molluscum contagiosum, genital warts
• Parasitic e.g. Scabies
• Fungal infection such as candida, tinea infection of the body
• Bacterial skin infection e.g. impetigo, recurrent and multiple abscesses
• Malignancies e.g Kaposi’s sarcoma (KS)
Non OIs HIV Related Diseases
• Drug reactions e.g. Steven Johnson syndrome
• Immunologic disorders/allergic conditions e.g. Psoriasis, Papular Pruritic Eruptions
Seborrhoeic dermatitis
Infections of Importance
• Syphilis
Syphilis is an STI and is found in relatively large number of HIV infected persons due
to fact that the means of transmission are similar and GUDs are a risk factor for HIV
acquisition and transmission
Clinical Features of Common OIs Affecting Respiratory System
Bacterial Pneumonia
• Common symptoms
Fever, chills
Cough
Shortness of breath
Purulent sputum
Abrupt start
Can occur at any CD4 count
Pneumocystis Pneumonia
• Occurs in patient with
CD4 count < 200
WHO stage 4 condition
• Common symptoms
Fever
Dry cough
Slow evolution
Progressive dyspnea
Tuberculosis
• Presentation may be a combination of cough, fever and sputum production
• Presentation may be atypical with dry cough, or no cough with fever only
• Excessive night sweats
• Loss of weight
• Chest pain
• Breathlessness
Clinical Features of Common OIs Affecting the CNS
Cryptococcal Meningitis
• Sub-acute onset of fever, headache, altered mental status
• Neck stiffness might be there or not at all
• The respiratory system may also be affected by Cryptococcus neoformans and present
with pulmonary symptoms e.g. cough and chest pain
• Often occurs in patients with CD4 count less than 50 cells/ml.
Note that, other conditions may cause altered mental state. These include
Cerebral malaria
Dehydration
Meningitis (TB/crypto/bacterial)
Toxoplasmosis
HIV encephalopathy
Psychosis
Cerebral Toxoplasmosis
• Generally occurs with CD4 count of less than 100 cells/ml
• Patients present with progressive focal neurological deficit
• There may also be convulsions, confusion and headache
• Alteration of mental state is rare
Peripheral Neuropathy
• This is a common HIV complication
• Usually symmetrical with stocking-glove distribution
• May be caused by
HIV itself
Drugs used in the treatment of HIV mainly Stavudine (d4T), didanosine (ddI) and
anti-TB drugs e.g. INH
Alcoholism
Diabetes
Clinical Features of Common OIs Affecting the GIT & Skin
Common OIs Affecting the GIT
• Oral Candidiasis (Oral thrush)
Occurs increasingly at CD4 < 300.
Presents with white painless plaques on the buccal, pharyngeal mucosa or tongue
surface that can easily be scraped off
• Oro-Oesophageal candidiasis
Caused by Candida albicans
Occurs in WHO stage 4
 May presents with difficult/painful swallowing and retrosternal pain. Other causes of
painful swallowing may include CMV and/or HSV lesions in the oesophagus.
• Diagnosis of oesophageal thrush is based on presentation and response to empiric
treatment.
• Treatment for thrush includes Nystatin mouthwash (dissolved in half glass water),
clotrimazole lozenges, and Fluconazole if oesophagitis or intractable oral thrush
Common OIs Affecting the Skin
• Herpes Simplex Virus (HSV)
Painful shallow ulcers/vesicles that can occur around the mouth or genital regions, but
can present anywhere on the body
Occur at any stage of CD4 count but increasingly as CD4 falls
HSV I and II occur at any CD4
Chronic HSV is seen when CD4 < 100
• HSV type 1 (oral herpes)
Cold sores around mouth and lips, but usually not the tongue
About 96% of people have antibodies to HSV type 1, though flare-ups are much more
common in HIV disease
• HSV type 2 (genital herpes)
Very painful sores around the genitals
• Kaposi’s Sarcoma-caused by human herpes virus type 8 (HHV – 8)
Kaposi’s Sarcoma
Common cancer in PLHIV aetiologically linked to Human Herpes Virus (HHV) type 8
but KS can also occur in HIV negative patients
• Can occur at any CD4 level
Diagnosis and Management
• Diagnosis made by observing characteristic lesions
• Lesions can be cutaneous, mucosal, or visceral involvement
• Confirmation requires examination of biopsy of the lesion
Management
• Less extensive disease responds to ART
• Refer patients with severe disease to a hospital especially if pulmonary disease is
suspected
• Radiotherapy and/or Chemotherapy is indicated for patients with rapidly progressive
disease
• Papular Pruritic Eruptions (PPE)
• Molluscum Contagiosum
• Seborrheic Dermatitis
Investigations & Treatment of Common OIs Affecting the Respiratory
System
Bacterial Pneumonia
• Investigations
Chest X-ray
Full blood picture
Gram stain and AFB stain of sputum if available
Most common pathogens
Streptococcus pneumonia
Hemophilus influenza
Staphylococcus aureus
• Treatment
Amoxicillin or Amoxicillin + Clavulanic Acid
Follow-up
See the patient in 3-5 days
PCP
• Investigations
Clinical examination and history is most helpful to reach a diagnosis
CXR may be done but can be normal or have generalized nodular opacities
Increased Serum Lactate Dehydrogenase enzyme in severe cases
Blood gas analysis
Pulse-oximetry to detectthe level of hypoxia
Induced sputum if available with silver staining to look for PCP
Note: Most of the investigations are not available in the primary health care facilities hence
referral is unavoidable after the pre-referral management.
Treatment
• High dose Cotrimoxazole at a dose of 12-15mg/kg body weight a day based on
trimethoprim component
• (The drug for a day should be in 3-4 divided doses)
• The dosage should also be for 21 days (3 weeks)
• Oxygen therapy
• Steroids e.g., Prednisolone may be used if there is severe hypoxia
Note: Patients suspected of having PCP should be referred to hospitals for proper
management and support for hypoxia. Pre referral management should always be done before
the patient is referred.
Tuberculosis
• Investigations
Laboratory examinations
AFB microscopy for sputum and aspirates
Gene Expert and Culture of sputum or aspirates for EPTB
Histological examination - Biopsy tissue
Chest X-ray (CXR) alone is not reliable as there is no X-ray appearance typical for
pulmonary tuberculosis (PTB)
Treatment
• Effective treatment requires the prescription of adequate chemotherapy including
Appropriate drug combinations
Drugs that are taken regularly
Drugs that are taken for a sufficient period of time
Beware of interactions with ART (e.g. Nevirapine and Protease Inhibitors with
rifampicin)
Investigations and Treatment of Common OIs Affecting the CNS
Cryptococcal Meningitis
• Suspected meningitis should be referred to hospital for proper investigations.
Investigations
• Lumbar puncture (LP)
Increased opening pressure
India ink staining may detect the yeast
In more advanced hospitals serum or cerebrospinal fluid cryptococcal antigen
(CRAG) may be done
Treatment
• Treatment needs to be done at hospital level.
• Cryptococcal Meningitis may be treated with:
Amphotericin B 0.7 mg/kg/day IV with or without Flucytosine 100mg/kg/day (in
divided doses) x 14 days during the induction stage
This is then followed by Fluconazole 400mg/day for 8 weeks in the maintenance
phase
Thereafter oral Fluconazole 200mg daily) until patient has sustained CD4 increase
greater than 200 for more than 6 months in the suppressive phase
In most resource limited countries, Amphotericin B and Flucytosine are not readily
available.
Alternatively, give intravenous (IV) Fluconazole 400mg/day x 10 days until patient
can take orally.
Then continue with the same dose for ten weeks.
Thereafter maintain 200mg daily.
Toxoplasmosis
• Investigations
The diagnosis is mostly clinical (though not very accurate)
Diagnostic investigations are done at hospital levels, therefore patients need to be
referred
Lumbar puncture which is usually normal excludes other causes of the clinical
presentations
In more advanced and well equipped hospitals serum toxoplasma antibodies may be
performed
Respond to treatment in 7-10 days
Differential diagnosis
Tuberculoma
Cerebral lymphoma
Cryptococcoma
• Treatment
Patients should be referred for proper evaluation and initiation of treatment
In acute cerebral toxoplasmosis treat with
Sulphadiazine 100-200mg/kg/day up to 1 gram in divided doses and
Pyrimethamine 50mg once daily (give 100 mg in the first day) and
Folinic acid 10mg daily as long as pyrimethamine is being given
For maintenance therapy, give
Sulphadiazine 1 gm two times a day
Pyremithamine 25 mg daily and folic acid 10 mg daily
In resource limited settings, the above mentioned drugs are usually not readily
available. Alternative treatment may include use of high dose cotrimoxazole or a
combination of sulfadoxine and pyrimethamine (SP).
Peripheral Neuropathy
• Treatment
Analgesic
Vitamin B (pyridoxine)
Consider amitriptyline or carbamazepine if pain is unresolved by the use of ordinary
analgesics
Usually improves with ART but avoid stavudine and didanosine as they may
aggrevate the condition as part of their side effects.
Treatment of Common OIs Affecting the GI Tract & Skin
Candidiasis
• Treatment
Nystatin mouthwash dissolved in half glass water
Clotrimazole lozenges
Fluconazole if oesophagitis or intractable oral thrush at a dose of 150mg/day or
200mg/day for 2-3 weeks
Herpes Simplex Virus (HSV)
• Treatment
Acyclovir shortens healing time
Given at a dosage of 400 mg 3 times/day for 10 days
Prophylaxis and Prevention of Common OIs
Cotrimoxazole in Adults
• Very effective in preventing PCP, toxoplasmosis, other pneumonias and diarrheal
diseases
• Is used for
All HIV-infected patients in WHO stage 2, 3, or 4
Asymptomatic HIV infected individuals with CD4 counts of < 350 cells/mm3
All patients with previous PCP and their CD4 count is still less than 350 cells/mm3
• Adult dose is 960mg (160mg Trimethoprim/800mg Sulphamethaxazole) daily given as 2
tablets of single strength of 480mg (80mg trimethoprim/400mg sulphamethaxazole) or 1
tablet of double strength 960mg when available
• Duration
Ongoing for patients not on ARVs
Stop when CD4 >350 for patients taking ARVs
Isoniazid Preventive Therapy (IPT)
• IPT is preventive therapy for TB
• It should be part of package for care people living with HIV
• Exclusion of active TB is vitally important
• Inability to exclude active TB may limit use of IPT
• Effective in HIV-infected people
• Can be given to people with HIV having high TB risk and have been screened to exclude
active TB disease
Prevention of Opportunistic Infections (OIs)
• Avoid unpasteurized dairy products, raw or undercooked eggs, meat, poultry, or fish to
avoid salmonella/shigella infections
• Avoid undercooked or raw meat for toxoplasmosis
• Family should be advised to boil drinking water to avoid diarrhoea diseases
• Avoid contact with bird droppings for cryptococcosis                                               
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