General Medicine Flashcards
Encapsulated bacteria (name 3)
Streptococcus pneumoniae
Haemophilus influenzae
Neisseria meningitidis
Risky organisms for post-splenectomy patients (other than encapsulated bacteria)
Malaria (+babesiosis)
E. coli + pseudomonas aeruginosa
Capnocytophagia canimorsus
What features suggest immunodeficiency?
Severe Persistent Unusual Recurrent infections.
Post-splenectomy management?
Antibiotic prophylaxis for 2y
Vax: Hib, niesseria, pneumococcus
Pt education re signs/symptoms of infections
Avoid malaria areas
Definition of Pyrexia of unknown origin
Fever >38.3 (>1 occasion) + >3w duration +no diagnosis despite >1w inpt investigations.
PUO subtypes
Classic
Nosocomial
Immunodeficient
HIV-related
Common causes of PUO
1/3-1/2 infections
1/4- neoplasms
1/10- CTD
Test for encapsulated bacteria?
Quellung reaction (capsular swelling)
How do we test for C. Dificile?
Detect toxin.
Appropriate tests for ?legionella
Detection of antigen in urine: positive early in disease but only detects serogroup 01.
Detect antibody serology: delay in diagnosis
Bronchoalveolar Lavage: invasive, low yield, but detects all stereotypes (NB special media needed)
Cultures: blood/sputum = unhelpful
What does CD4+ T cell count predict in HIV?
Current susceptibility to opportunistic infections
What do you measure in HIV to assess stage of disease?
CD4+ T cell count
Plasma HIV RNA load
What does plasma HIV RNA load predict?
The rate of decline in CD4+ T cell count.
CD4+ count: 600. Likely infections present?
No infections seen if >500
CD4 T cell count 200-500 likely infections?
HSV
VZV
Oral candida
Progressive stage of disease
CD4+ T cell count if pneumocystis infection?
CD4+ <200
CD4+ count if oral candida?
200-500
CD4 count when crytococcus infection
<200
Infections likely when CD4+ T cell count <200?
TB Pneumococcus Salmonella Pneumocystis Cryptococcus Oesophageal candida Toxoplasma Cryptosporidium Isospora
Infections likely when CD4+ <50?
Mycobacterium avium intracellulare
Progressive Multifocal Leuko-Encephalopathy
CMV