Respiratory Flashcards
Ipratropium bromide in the management of acute asthma exacerbations in paediatric patients
Ipratropium bromide, in addition to salbutamol and prednisolone, did not significantly reduce admission rates for children with a moderate asthma exacerbation.
A nine-year-old boy presents with a two-week history of cough, tachypnoea, recession and increasing cyanosis. The chest X-ray and a lung biopsy (stained with methenamine silver nitrate) are shown. The underlying immune deficiency is most likely to be primarily affecting his:
Methenamine silver nitrate is used to stain for fungi and Pneumocystis carinii. Pneumocystis is a genus of unicellular fungi.
Clinically - CXR shows widespread pulmonary infiltrates. Another clinical finding is that arterial oxygenation is often strikingly lower than would be expected from symptoms.
PCP is identified by staining of cysts with methenamine silver nitrate, or toluidine blue, which stains dark bodies within the cysts.
Pneumocystis pneumonia is a well-recognised major opportunistic infection in HIV-positive individuals. Similar to other opportunistic fungal infections, Pneumocystis pneumonia is most often observed when the CD4+ T helper cell count falls below 200 cells/mm3. CD4+ T cells are absolutely critical for resolution of Pneumocystis, having an essential role in the recruitment and activation of effector cells against the organism.
The most common pathogen associated with protracted bacterial bronchitis in children is which of the following?
In protracted bacterial bronchitis (PBB) (often referred to chronic suppurative bronchitis), H. influenzae is the most common organism found (non-typeable; 28–58% of children), then Streptococcus pneumoniae (13–58%) and Moraxella catarrhalis (17–59%). The diagnosis of PBB was formalised by Australian researchers in 2006, where the microbiology was also similar: HIB (47%), S. pneumoniae (35%) and Moraxella (26%). The most widely used antibiotic is oral amoxicillin-clavulanate, as it is active against beta-lactamase-producing strains of H. influenzae.
A three-year-old girl presents to the Cystic Fibrosis clinic for annual review. She has grown Staphylococcus Aureus on her sputum culture for the first time. You admit her for intravenous antibiotic therapy with the aim of eradication. On discharge, you need to decide which antibiotic to use for ongoing prophylaxis.
Staphylococcus aureus is the most common organism grown in toddlers. Flucloxacillin is the most appropriate antibiotic coverage for Staphylococcus aureus and can be used at a low dose for ongoing prophylaxis.
A 16-year-old girl presents to the Cystic Fibrosis clinic for annual review. She has grown Burkholderia cepacia on her sputum culture for the first time. You admit her for intravenous antibiotic therapy with the aim of eradication. On discharge, you need to decide which antibiotic to use for ongoing prophylaxis.
Trimethoprim-sulfamethoxazole has the best coverage for burkholderia cepacia and has good oral absorption.
A 14-year-old boy presents to the cystic fibrosis clinic for annual review. He has grown pseudomonas aeruginosa on his sputum culture for the first time. You admit him for intravenous antibiotic therapy with the aim of eradication. On discharge, you need to decide which antibiotic to use for ongoing prophylaxis
Pseudomonas aeruginosa is most commonly grown in adolescent patients. Ongoing prophylaxis with inhaled tobramycin is the safest way to continue prophylaxis. Ciprofloxacin can be used but is has more systemic effects and is not as well tolerated.
A 12-year-old boy with cystic fibrosis presents with a six-week history of increased cough and some wheeze. He has received a two-week course of oral amoxycillin-clavulanic acid, followed by two weeks of oral ciprofloxacin without any improvement.
CXR shows pulmonary infiltrates, consolidation, central bronchiectasis and collapse. These findings are present despite two weeks of augmentin and two weeks of ciprofloxacin.
Allergic broncho-pulmonary aspergillosis.
ABPA should be suspected if patients with pulmonary infiltrates or clinical deterioration do not respond to one week of antibiotic treatment.
The minimal diagnostic criteria:
Acute or subacute clinical deterioration (cough, wheeze, exercise intolerance, exercise-induced asthma, decline in pulmonary function, increased sputum) not attributable to another etiology.
Total serum IgE >1200 ng/mL (if total IgE is 480 to 1200 ng/mL, repeat testing in one to three months; if the patient is taking steroids, repeat when steroid treatment is discontinued).
Immediate skin test reactivity to Aspergillus or in vitro presence of anti-Aspergillus IgE antibodies.
Plus one of the following:
Serum precipitins or IgG antibody to A. fumigatus
New or recent abnormalities on chest x-ray (infiltrates or mucus plugging) or chest CT (bronchiectasis) that does not clear with antibiotics and physiotherapy
Following a normal pregnancy a male infant has a normal vaginal delivery at term in the presence of clear liquor. Immediately following delivery, he is in severe respiratory distress with marked subcostal and sternal recession. A normal cry is heard. A soft, high-pitched, biphasic stridor is audible. The most likely cause of this infant’s respiratory distress is:
bilateral abductor vocal cord paralysis: normal cry, with severe inspiratory stridor.
laryngo-oesophageal cleft: expect and absent or weak cry
would be no stridor with a lingular cyst.
severe laryngomalacia: present as stridor exacerbated with crying.
unilateral vocal cord paralysis: hoarse and weak voice. Stridor and retractions are not marked. There can be choking during feeds.
