Respiratory System quiz #4 high-yield review

medbullets.com link to summary:
Tuberculosis

– Streptomycin blocks protein synthesis by binding to the bacterial lysosome. Ethambutol is bacteriostatic and effects cell wall synthesis – very bad side effects/toxicity is optic neuritis.

– INH (Isoniazid) must be prescribed with vitamin B6 (pyridoxine).

The side effects of TB drugs:

– Ethambutol is VISUAL IMPAIRMENT (optic neuritis) (“Ethan got hit with a bottle in his eye and now he can’t see”)
– Isoniazid, Rifampicin, Pyrazinamide is JAUNDICE & VOMITING (“all make you throw up!”)
– Streptomycin is DEAFNESS / DIZZYNESS (“stripped of the ability to hear”)
– Rifampicin is RED / ORANGE URINE (“R – Red..Ribena juice..its not red but close enough for a memory aid!”)
– Isoniazid is PERIPHERAL NEUROPATHY (burning feet) (No memory aid – so just frggin remember this!)
– Pyrazinamide is HYPERURICEMIA (joint pains) (“Pyra – sounds like HYPER..uricemia)

Complications:
– Bronchiectasis
– Hemoptysis

KNOW TB Drugs and Two Types of resistance:

Multidrug-Resistant TB (MDR TB)

Multidrug-resistant TB (MDR TB) is caused by TB bacteria that is resistant to at least isoniazid and rifampin, the two most potent TB drugs. These drugs are used to treat all persons with TB disease.

TB experts should be consulted in the treatment of MDR TB.

Extensively Drug-resistant TB (XDR TB)

Extensively drug-resistant TB (XDR TB) is a rare type of MDR TB that is resistant to isoniazid and rifampin, plus any fluoroquinolone and at least one of three injectable second-line drugs (i.e., amikacin, kanamycin, or capreomycin).

Because XDR TB is resistant to the most potent TB drugs, patients are left with treatment options that are much less effective.

XDR TB is of special concern for people with HIV infection or other conditions that can weaken the immune system. These people are more likely to develop TB disease once they are infected, and also have a higher risk of death once they develop TB.

TB experts should be consulted in the treatment of XDR TB.

INH
I = Isoniazid
N = neurological problems: SZ, CNS, neuropathy
H = hepatotoxic

– Know about the PPD/Mantoux induration
Normal people > 15 mm
10 mm: High-risk population, ie. homeless, prisoners, healthcare workers, EtOH, DM, etc
5mm induration = HIV, steroid users (like COPDers, or Lupus , asthma, etc), organ transplant recipient.
It is the INDURATION, not the redness.

————————————————————————-

SARS

Source: www.Osmosis.org

Severe acute respiratory syndrome (SARS) is a viral respiratory disease of zoonotic origin caused by the SARS coronavirus (SARS-CoV). Initial symptoms are flu-like and may include fever, myalgia, lethargy symptoms, cough, sore throat, and other nonspecific symptoms. The only symptom common to all patients appears to be a fever above 38 °C (100 °F). Shortness of breath may occur later. The patient has symptoms as with a cold in the first stage, but later on they resemble influenza. SARS may occasionally lead to pneumonia, either direct viral pneumonia or secondary bacterial pneumonia.

Sample case:

1. A 42-year-old man presents to the emergency department with a 3-day history of fever, chills, headache, non-productive cough, myaglias, dyspnea, and diarrhea. He states that he returned 5 days ago from an area of China with a recently documented cluster of SARS cases, where SARS-infected animals are believed to be located. He is hypoxic, and the initial chest radiograph reveals multifocal bilateral infiltrates. Laboratory tests show moderate lymphopenia, and thrombocytopenia, and elevated creatine kinase and liver enzymes. He is transferred to the ICU and over the next 30 days he gradually improves, developing secondary bacterial infections during his stay in the ICU.

2. A 64-year-old doctor from China presents to a hospital in Hong Kong with a week history of fever, headache, dry cough, and worsening shortness of breath. He is in Hong Kong on business. The patient is a family practitioner and there is a history of contact with an unprecedented number of patients presumably suffering from influenza. Temperature is 102°F (39°C).  The patient is admitted to the ICU with contact isolation. He expires shortly thereafter. PCR assay of the post-mortem lung is positive for SARS-CoV. The local health authorities are notified.

SOURCE:

– Mostly elderly people suffering from SARS have a greater risk of developing pneumonia, heart and liver failure, and sometimes respiratory failure as a result of the progression of the disease.

– The SARS virus can survive and remain viable for around 6 hours when left in the open.

– Studies have shown that around 60% of deaths occurring due to SARS were among individuals over 55 years.

– Antibiotics are generally not used in the treatment of SARS as it is caused by a virus, not bacteria. However, sometimes antibiotics may be needed to treat pneumonia and other bacterial infections that may occur due to SARS.

– The specific diagnostic tests for SARS are the antibody tests for SARS, the PCR test and direct isolation of SARS virus.

– SARS causes atypical pneumonia as a complication.

– After recovery, some patients affected by SARS have shown the presence of femoral necrosis, pulmonary fibrosis, and even osteoporosis.

—————————————————————-

RSV

– Bronchiolitis
– Hypoxia
– Tx is O2 and fluids
– Prevention is best
– Palivizumab
– monoclonal antibody
– blocks F protein
– Ribavirin studies have been inconclusive
– Epithelial infection is mediated by protein G. while protein F causes infected cells to fuse and form syncytia, hence the name RSV
– Human respiratory syncytial virus is a negative sense strand RNA virus.
– The target of the monoclonal antibody palivizumab is the respiratory syncytial virus F protein
– Human respiratory syncytial virus is a (family) Pneumoviridae

Which member of the paramyxovirus family can cause very serious croup?
a) Measles
b) Meta pneumo virus
c) Hendra
d) Respiratory syncytial virus (RSV)

How are all the important human paramyxoviruses transmitted?
A) By direct contact with infected rodents
B) By respiratory droplets
C) By the bite of an infected arthropod
D) By sexual transmission
E) By contaminated food

A giant, multinucleated cell that has cytoplasmic inclusion bodies is also known as a what?
A) Syncopate
B) Syncytium
C) Syncline
D) Synchrotron
E) Syndrome

Source: www.Osmosis.org

A 4-month-old infant is brought to her pediatrician due to fever, cough, and wheezing for the past day. She was born prematurely at 31 weeks, and her mother states that she has not had a previous illness and that there are no familial diseases that she is aware of. Physical examination reveals subcostal retractions and nasal flaring. A plain film chest radiograph shows diffuse hyperexpansion, bilateral interstitial infiltrates and bilateral upper lobe atelectasis. Which of the following is a major feature of the pathogen causing this patient’s symptoms?

A Complement system disruption
B Frequent antigenic shifts
C Fused respiratory epithelial cells
Syncytia formation (fusion of epithelial cells into a large giant cell) is a hallmark feature of respiratory syncitial virus (RSV), a virus responsible for most cases of childhood pneumonia infections.
D Profound viremia
E Secretion of IgA protease

A 7-month old boy comes to the office because his mother notices that he seems to be having difficulty breathing. She says that the patient has had rhinorrhea, watery eyes, and a dry cough for the last three days. This morning, the mother noticed the infant working harder to breathe. Sick contacts include two children in daycare with viral illnesses. Home medications include vitamin D supplementation. The patient has no known drug allergies. Physical examination shows increased work of breathing with tracheal tugging, nasal flaring, and intercostal and subcostal retractions. His temperature is 37°C (98.6°F), pulse is 160/min, respirations are 40/min, blood pressure is 90/55 mm Hg, and oxygen saturation is 85% on room air. He has diffuse wheezing in both lung fields. His mother states that this is the first time this has happened to her child. Which of the following is evidence-based management for this patient?

A Continuous pulse oximetry with supplemental oxygen therapy
For bronchiolitis management, current guidelines state that supplemental oxygen should be given, along with continuous pulse oximetry to monitor response to therapy.
B Prednisolone
C Chest radiograph
D Hypertonic saline nebulization
E Leukotriene inhibitors

———————————————————————————————

Pulmonary embolism

– mutation

From Medbullets.com:

Risk factors

  • Virchow’s triad
    • stasis
      • immobility
      • CHF
      • obesity
      • surgery
    • hypercoagulability
      • pregnancy
      • OCP
      • protein C/S deficiency
      • factor V Leiden
      • severe burns
      • cancer
    • endothelial damage
      • exposed collagen stimulates clotting cascade
        • trauma
        • fracture
        • previous DVT

– hereditary antithrombin deficiency
– rt heart failure (RHF)
– Estrogen probs…
– site of origin?
– saddle embolism — rt. heart failure
– Bronchial artery supplies lungs
– tachypnea, hypoxia
– Sx: pleuritic pain, wedge-shaped infarction

– heparin, warfarin, TPA
– big problems caused by antithrombin and protein C
– check for atrial septal defect (b/c clot could go to brain!)

———————————————————-

Pulmonary hypertension

– the balance between BMPR2 (stops cells proliferating) and TGFB (makes them grow).
– decr. end diastolic volume, syncope, hypoxia
– idiopathic PAH, no cure
– 6 min walking test
– check calcium channel blockers
– primary vs. secondary

 

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s