HIV and the Lung Flashcards
Lung conditions assoc. w. bacterial infection in HIV (3)
bronchitis
bronchiectasis-often secondary to bacterial/mycobacterial/PCP infection
pneumonia
Organisms assoc. w. bronchitis in HIV (2)
strep pneumoniae-commonest cause of pneumonia in HIV
haemophilus
commonest organisms causing pneuomnia in HIV (4)
strep pneumoniae
haemophilus
staph aureus
mycobacterium avium intracellulare (ethambutol+clari+rifabutin)
CXR features of pneumonia in HIV
atypical-mimicks PCP in 50% of cases (diffuse bilateral infiltrates)
Presentation of PCP (4)
non-productive cough
progressive exertional dyspnoea
+/- fever/night sweats
pneumothorax
(NB normally occurs when CD4 <200)
(if CD4<200, prophylactic Abx are given)
Dx of PCP (4)
(auscultation usually normal, can have end-inspiratory crackles)
CXR
CT chest (nodules and cysts) if CXR normal but still clinically suspicious
induced sputum sample or bronchoscopy if still unsure:
- nebulised saline/BAL
- Grocott’s stain/silver stain shows Mexican hats
desaturation on exercise
CXR features of PCP (6)
initially normal
bilateral perihilar interstitial infiltrates:
- ground glass shadowing
- hazy shadow through which lung markings can be seen
diffuse alveolar shadowing
upper zone infiltrates resembling TB
peri-hilar lymphadenopathy
intrapulmonary nodes
Rx of PCP (3)
1st line: co-trimoxazole
if PaO2=/<9.3: IV/PO steroids to prevent drop in sats on initiating Rx
2nd line: clindamycin+primaquine (NB primaquine CI in G6PD)
SEs of co-trimoxazole (2)
marrow/nephro/hepatotoxicity
20% develop mac-pap rash
PCP prophylaxis and criteria (5)
co-trimoxazole
give if:
- CD4<200
- other AIDS-defining condition
- previous episodes of PCP
continue prophylaxis until CD4>200 and undetectable viral load for 3mo
Features of pulmonary cryptococcosis (2)
can be primary infection secondary to disseminate disease e.g. cryptococcal meningitis
can cause disseminated disease e.g. skin nodules
Dx of pulmonary cryptococcosis
identify organism in respiratory secretions
Rx of pulmonary cryptococcosis
fluconazole
Features and presentation of histoplasmosis (4)
occurs as part of disseminated disease
presentation:
- subacute fever and wt. loss
- dyspnoea
- dry cough
Dx of histoplasmosis (2)
BAL
lung biopsy
Rx of histoplasmosis
liposomal amphotericin
RFs for aspergillosis (2)
neutropenia
corticosteroid use
(rare, even in HIV+ve)
Presentation of aspergillosis (3)
non-specific
pleuritic chest pain
haemoptysis
Rx of aspergillosis (2)
voriconazole
liposomal amphotericin
Features and Rx of influenza infection in HIV (2)
not more common in HIV but is more severe
Rx w. oseltamivir if Sx =/<48hr
Features and Dx of CMV infection (3)
Pneumonitis
CD4<100
Dx by isolating inclusion bodies in BAL/lung tissue
Features of KS (2)
always accompanied by lymphadenopathic/cutaneous KS
may regress w. cART
Features of bronchial carcinoma in HIV (2)
2-4 times more likely in HIV+ve smokers
presentation is often w. disseminated disease
Features and Rx of non-specific pneumonitis (2)
mostly self-limiting
prednisolone may be beneficial
Features of lymphocytic interstitial pneuomonitis (2)
mainly affects children
mimics IPF: slowly progressing dyspnoea and cough
Other non-infective, non-malignant conditions HIV patients are at increased risk of (3)
COPD
Pneumothorax
Pulmonary artery HTN: 6-12 times more common
Presentation of TB in HIV (2)
often atypical
disseminated disease more common
(if HIV+ve pt. has cough/fever/night sweats>HIV until proven otherwise)
CXR features of TB in HIV (3)
classical upper zone cavitations replaced with:
- pulmonary infiltrates
- mediastinal lymphadenopathy
- pleural effusions
Histology of TB in HIV (3)
poorly formed granulomas
less caseation
fewer acid-fast bacili present
Rx of TB in HIV (3)
(NB drug resistance more common in HIV)
RIPE-4for2, 2for4
beware drugs which are metabolised by P450 as rifampicin>reduced cART efficacy>worse HIV control
rifabutin is an alternative with less of an effect on P450
Features of IRIS (3)
occurs when cART and TB Rx are commenced soon after each other
improvement in immune response>worsening TB Sx
cART can unmask unknown TB which manifests a few wks after commencing cART
(therefore may be worth delaying cART for 1-2mo after TB Rx started)
Major criteria for IRIS (4)
new/worsening:
- LNs/cold abscesses/focal tissue involvement
- radiological features
- CNS TB
- serositis
(NB other reasons for worsening Sx need to be ruled out e.g. non-adherence)
Minor criteria for IRIS (3)
new/worsening:
- constitutional Sx
- resp Sx
- abdo Sx
