9. Role of clinical laboratory test in the diagnosis of respiratory diseases (including investigations for allergy and autoimmunity) Flashcards
All the 24 lab parameters that could tell us something about pulmonary pathology
cultures also incuded, antibodies also included
- CBC
- ABG
- CRP
- ESR
- Procalcitonin
- D-Dimer
- Platelet count
- Troponin
- BNP and Nterminal Pro-B
- Sputum Cultures
- Respiratory Viral Panel
- Blood Cultures
- Tuberculin Test
- Ferritin
- Coagulation Panel [PT/INR, APTT]
- Folate and Vit B12
- Thyroid Function Test
- HbA1C
- Alpha-1 Antitrypsin
- IgE
- IgG, IgA, IgM
- Autoantibody tests
- ANA test
- RF and Anti-CCP test
Role of CBC
Leukocytosis may indicate infection or inflammation
Anemia can be detected by the hematocrit (amount of RBC) and hemoglobin level
Role of ABG
Assess for hypoxemia or hypercapnia and gives information about lung function
Role of CRP
indicates a systemic inflammatory process usually detected in lung infections and autoimmune conditions
Role of ESR
Rate at which RBCs settle in a vertical tube
Its increase can indicate infection, inflammation, malignancies, autoimmune diseases
Role of Procalcitonin
acute phase reactant that can help differentiate bacterial from non-bacterial causes of lower respiratory tract infection
Role of D-DImer
fibrin degradation product that can indicate presence of blood clotting conditions like DVT and Pulmonary Embolism
Role of Platelet Count
help evaluate for thrombocytosis which can be associated with certain lung conditions (eg. Tuberculosis)
Role of Troponin
used to rule out myocardial infarction when chest pain is a symptom
Role of BNP and N-terminal pro-B
Assess heart function in case of congestive heart failure and cardiopulmonary conditions. Elevated values indicate heart failure
Role of Sputum Cultures
Identify microbiological organisms causing an infection and test for antibiotic resistance
Role of Respiratory Viral Panel
PCR assay that can detect specific viral nucleic acids in patients with signs and symptoms of respiratory infection. Positive result may indicate asymptomatic infection or recently resolved infection
Role of Blood cultures
to identify bacteria and fungi in blood stream and test for antibiotic
resistance
Role of Tuberculin test
In case of suspicion of tuberculosis and confirm if patient has antibodies or was previously vaccinated against TB
Role of Ferritin
measures iron stores and may be elevated in cases of chronic inflammation, sarcoidosis and hemochromatosis
Role of Coagulation Panels
evaluates coagulation and is relevant in cases of pulmonary embolism and bleeding disorders
Role of Folate and Vit B12
assess for nutrients and presence of anemia causing dyspnea and fatigue signs
Role of Thyroid Function Test
assess function of thyroid gland which can influence breathing
and lung health
Role of HbA1C
evaluates glucose control in diabetic patients which can influence
lung function
Role of Alpha-1 Antitrypsin
Deficiency is associated with a genetic disorder that causes emphysema
Role of IgE
Elevated levels are associated with allergic conditions and asthma
Role of IgG, IgA, IgM
Assess immune function and immunodeficiencies
Role of Antibody testing
detects antibodies targeting self antigens in autoimmune diseases targeting the lungs (Sjogren Syndrome (Anti-SSA,SSB), Systemic Sclerosis (Anti-Scl-70), ANCA associated vasculitis, Goodpasture’s Syndrome (anti-GBM))
Autoimmune conditions give ILD manifestations and can be a cause of recurrent inflammation in lungs
Role of ANA test
Screens for Systemic Lupus Erythematosus
(SLE) which is an autoimmune disease that may have pulmonary manifestations (pleuritis, ILD, pulmonary hypertension)
Role of RF and Anti-CCP test
Rheumatoid arthritis may have pulmonary manifestations like interstitial lung disease, pleurisy and rheumatoid nodules.
Methotrexate used to treat Rheumatoid Arthritis can result in methotrexate induced pneumonitis which presents with lung inflammation and can lead to symptoms like cough, shortness of breath and fever
