Tuberculosis Flashcards
Tuberculosis
Overview:
mycobacterium tuberculosis
oldest disease to affect humans
top causes of infectious death worldwide
common disease among HIV infection worldwide
95% reported from developing countries
epidemiology in the united states
adults > 65 have the highest incidence rate per capita
adult members of the infected population
20-25 % HIV-related mortality
the leading cause of death in the HIV population
foreign-born population
disadvantages or marginalized population
Tuberculosis stages
Primary TB :
limited to no clinical
limited infection and spread of the disease
progressive - primary TB:
inadequate immune response to contain the primary
infection
1/3 of new cases of TB caused by person-to-person
Latent TB :
Do not have active disease
cannot transmit
Active TB :
reactivation of the disease
latent not adequately treated
contagious
tuberculosis exposure to infection
Transmission:
A person with infected pulmonary TB
Small diameter
suspended in the air for several hours
high risk to transmit
crowding in poorly ventilated rooms
highly infectious :
TB patients with AFB containing sputum
cavitary pulmonary diseases
TB clinical manfistations
constitutional symptoms
fever, night sweats, weight loss, anorexia, general malaise, and weakness
Hemoptysis:
20-30% of patients
pleurtic chest pain and dyspnea
ARDS
CBC findings
mild anemia, leukocytosis, and thrombocytosis elevated ESR and CRP
BMP findings
hyponatremia
clinical work up extrapulmonary
tuberculosis lymphadenitis
most common presentation in HIV patients
lymph nodes matted non-tender mass
diagnosis established by FNA biopsy
Pleural effusion:
fever ,pleuritic chest pain and dyspena
thoracentesis
Pleural fluid :
straw-colored exudate
protein concentration > 50%
normal / low glucose concentration
PH 7.3
AFB rarely seen on direct smear
cultures can be a false negative
skeletal TB
lower thoracic and upper lumbar vertebra
most common
Paraparesis:
medical emergency
requires rapid drainage
Hip joints involve the femur head of the femur
infected knee will produce pain and swelling
diagnosis-based synovial fluid:
thick appearance, high protein concentration
variable cell count
tuberculosis meningitis
rare in adults
occurrence in HIV
Clinical findings :
Headache, AMS, low-grade fever, malaise, anorexia, irritability, confusion, lethargy, neck rigidity
Diagnosis:
Lumbar puncture is the cornerstone
CSF high WBC with lymphocytes
neutrophils in the early stage
protein 1-8
low glucose concentration
CSF culture :
diagnostic up to 80% of cases
remains gold standard
pericardial TB
develop frequently in HIV
fatal if not treated
high-risk group
high-risk country
clinical findings:
sub acute with dyspnea , feer dull retrosternal pain and pericardial friction rub
diagnosis;
pericardiocentesis
exudative, high lymphocytes, and monocytes
pericardial fluid culture
mycobacterium tuberculosis is identified in 66%
pericardial biopsy has higher yield
Genitourinary TB
abnormal UA with pyuria and hematuria
Culture negative pyuria in acidic urine:
Suspect TB !!!!
urinary frequency, dysuria, nocturia, hematuria, and flank pain
Pyelography or ABD CT scan:
deformities and Obstrucions
Calcifications of urinary structures
TB diagnosis
abnormal chest X-ray findings
highly sensitive, poor specificity
rapid imaging technique
diagnosis
require recovery of M tuberculosis
cultures or DNA / RNA amplification trechinques
three consecutive specimines ( sputum)
Xpert MTB/RIF assay
fully automated real-time nucleic acid amplification
highly sensitive and specific
detect TB and rifampin resistance
TB treatment
susceptible strains curable in the vast majority
fatal within 5 years in 50-65% of cases if not treated
two main aims of TB TX
1. prevent morbidity and mortality while preventing resistance
2. make patients noninfectious to others
became possible in 1943
discover of streptomycin
monotherapy developed resistance
treatment failure treatment
new TB treatments
6 month duration of treatment;
intensive phase ( bactericidal)
2 months treatment:
isoniazid ( 5mg kgday )
rifampin 10mg kg per day)
pyrazinamide ( 25mg kg day)
ethambutol ( 15mg kg day )
Continuation phase:
4-month treatment ( sterilization)
isoniazid 5mg dk day
rifampin 10mg kg per day
TB-MDR
bedaquiline and delamanid
