Pulmonology: Respiratory Illnesses

Acute Bronchitis

-              Respiratory virus (MCC)

-              MCC of hemoptysis besides lung cancer

-              1-3 weeks

Presentation: winter months, respiratory viruses, cough, afebrile, rhonchi that clear w/ coughing

No CXR indication

RSV (includes all info, esp. what type of virus and vaccine schedule) 

-              Paramyxovirus

-              Leading cause of bronchiolitis (inflammation of the small airways in the lung) and pneumonia in children under 1

Risk Factors: infants under 6 mo, infants under 1 yr who were premature or exposed to 2^nd hand smoke

Transmission: direct contact w/ inoculation of mucous membranes (eye to mouth type) 

Sx:

-              URI: rhinorrhea, watery eyes, pharyngitis

-              LRI: cough, SOB, wheeze

Dx: PCR

Tx: supportive (O2, Tylenol), very sick: antivirals like ribavirin or IVIG

Vaccine: all infants born in cold/flu season or entering their first cold/flu season receive a dose, pregnant moms sept-jan 32-36 weeks, at risk 60+, everyone over 75

Acute Bronchiolitis (who is most at risk?) 

-              Inflammatory processes that affect the bronchioles, COPD-like rxn

-              MCC in 2 mo to 2 yrs= RSV

-              URI prodrome LRI: like a cold  to bam very bad days 3-5 (wheezing, cyanosis)

o   Pulse ox a good indicator in kids

Dx= clinical

Tx: supportive (O2, hydration, antipyretics)

-              Premature babies or underlying immunodeficiency or heart/ lung disease: Palivizumab (monoclonal antibody)

Croup (type of virus, indicative sign, treatment) 

-              Caused by a parainfluenza virus, leads to upper air way obstruction due to larynx, trachea and bronchi swelling  inspiratory stridor, hoarseness, barking cough

-              Clinical Dx

-              Steeple sign on CXR from laryngeal narrowing

Dexamethasone, nebulized epinephrine in severe cases

Pertussis: What causes it?

-              Caused by Bordatella pertussis, gram – aerobic encapsulated coccobacillus

Pertussis: 3 phases

1.        Catarrhal: 1-2 weeks of non-specific malaise, rhinorrhea, cough, lacrimation

2.        Paroxysmal: 2-3 months of paroxysmal (episodic) cough and whooping, often with proceeding emesis, may be worse at night

3.        Convalescent: 1-2 weeks of gradual decrease in frequency and severity

Pertussis: diagnosis 

-              First 2 wks of sx: culture from nasopharyngeal swab or PCR blood sample

-              More than 4 weeks: serum PCR

-              Can be clinical (with such a characteristic cough)

-              Elevated white counts

Pertussis: treatment and vaccination

Tx:

-              Macrolides w/I 3 weeks of sx onset, use Bactrim if allergic

Vaccination

-              Peds: 5 doses DTap (w/ diptheria and tetanus)

-              11-18 y/o: Tdap booster

-              One dose Tdap recommended: 19+ w/o adolescent booster, pregnant moms

What are the types of influenza?

-              Influenza A (typically more severe), influenza B (typically less severe, more GI sx)

o   Contain hemagglutinin and neuraminidase on their surfaces (think H1N1)

How is influenza transmitted? What is the incubation period? What are the contagious periods?

Transmission: respiratory droplets w/I 6 feet

Incubation: 2 days, quicker in the unvaccinated

Viral shedding/contagious period:

-              24-48 hours before sx start to 1 week after symptoms start

-              Can be basically immediately

-              More sick= more contagious

-              Return to life… 24 hours w/o fever w/o antipyretics

What are flu sx? What is a severe complication of the flu? What are two causative agents of that complication?

Sx: fever, chills, aches, fatigue, confusion, pharyngeal erythema, mild cervical adenopathy

( can be mild to severe)

Complication: Pneumonia

-              Higher risk in those over 65, immunocompromised, comorbidities

-              Secondary bacterial pneumonia

o   MC= pneumococcal pneumonia

o   Staph aureus= most serious

When do we test for the flu? How?

-              Only test when it will impact treatment (hospitalization, underlying disease, comorbidities)

-              Testing Types:

o   Gold standard: PCR (not realistic)

o   Most common/preferred: nucleic acid amplification tets (NAAT), can distinguish A and B

o   RIDT and viral culture: less common

Describe influenza treatment and the 48 hour guidelines

-              Give neuraminidase inhibitor: oral oseltamivir (Tamiflu) w/I 48 hours of Sx

-              After 48 hours, give if

o   Hospitalized

o   Severe or high risk

o   Healthcare workers

o   Household w/ high risk

-              Can administer tamiflu prophylactically in ages over 1 in high risk groups 1-2 weeks after exposure: daycare, LTC, hospitals to PREVENT OUTBREAKS

-              Have mRNA synthesis inhibitor (zofluza) way less commonly used

Describe vaccination criteria and types for influenza

-              Every 6 months and older w/o contraindications by end of October, annually

o   NOT egg allergy (used to be but not anymore)

o   History of guillian barre syndrome w/I 6 weeks of previous influenza vax

o   Younger than 6 mo

o   Severe allergic rxn

-              Kids 6mo-8y/o w/ first flu vaccine: get a second dose 28 days later (also if previously they only got 1 dose in the past)

Vaccine types:

-              Inactivated influenza vaccines (IIVs, fluzone): egg based, quadrivalent (2 forms of A, 2 forms of B), use trivalent when quad is unavailable (2 and 1)

-              Recombinant influenza vaccine (RIV4): Flubok, 18+, flu proteins

-              Live attenuated influenza vaccine (LAIV): flumist non-pregnant, 2-49y/o

o   NO FLU MIST: not 2-49, under 5 w/ history of asthma/wheezing, pregnant, immunocompromised (could make them sick)

What is TB? How is it spread? Where does it go in the body?

-              Mycobacterium tuberculosis, acid-fast bacillus

-              Leading cause of death worldwide from an infection

Spread: aerosolized microdroplets, longer exposure= more likely to get it

Location: MC is lungs, larynx 2^nd, can go basically anywhere in the body

Differentiate active/latent TB and primary and secondary infections.

Primary disease: rapid progression from getting infected to having active disease

-              Located in middle/lower lobes

Secondary/REACTIVE disease: disease onset after latency

-              Tends to be in the apex of the lungs

Active TB: immune system is not containing TB infection, causing symptoms, infectious

Latent TB infection: infected w/ TB but not infectious to others, asymptomatic, immune system is containing the infection

What is the pathophysiology of a TB infection? Describe 3 places it may manifest and the specific disease name.

in fection causes delayed HS reaction type IV, creating caseating (central necrosis) granulomas, can do to any organ

o   Scrofula: TB in cervical lymph nodes

o   Pott disease: TB in vertebrae

o   Miliary TB: no central necrosis

Tb Diagnosis 

-              Imaging CXR (diff location-middle/lower vs upper, miliary looks different)

-              3 sputum samples on 3 consecutive days for

o   Acid-fast bacilli staining (rapid, inexpensive)

o   Culture (takes weeks)

o   NAAT (48 hours)

-              +NAAT=TB, -NAAT= cannot exclude TB, wait on culture

TB Screening

o   Mantoux tuberculin skin test (PPD)

§  Read 48-72 hours later, measure size of induration (bubble) not redness

o   TB Gold Assay Blood Test:

§  Do if they’ve had the vaccine

o   GET CXR if either are positive

When is a TB skin test contraindicated?

When someone has had the vaccine (endemic countries)

Treatment of latent TB

-              If we find latent TB (positive PPD, normal CXR)

o   3-4 months of rifampin plus or minus isoniazid

o    OR less preferred: isoniazid and B6 for 9 months

Treatment of Active TB

-              ACTIVE TB: AFB or NAAT +

o   Respiratory isolation for 2 weeks, observe medication taking

o   RIPE treatment              

§  Rifampin (red secretions) 6 mo

§  Isoniazid 6mo

·      Inhibits vitamin B6  neuropathy B6 supplement

·      Hepatitis or neuropathy

§  Pyrazinamide 8 weeks

·      Hepatitis or hyperuricemia (NOT IN PREGNANT WOMEN-DO OTHER 3 FOR 9MO INSTEAD)

§  Ethambutol 8 weeks

·      Optic neuritis (E=eyes), neuropathy