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What is involved? (including coding of cases) SABRE Case Studies and Information
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Case Study: Psittacosis
A
43 year old non-smoking farm worker presented with a 2 week history of
non-productive cough, breathlessness, fevers and fatigue. A chest X ray showed
right upper lobe consolidation compatible with pneumonia. His GP treated him
with amoxycillin. After a week, he felt worse, with increasing dyspnoea,
confusion and malaise, and he went to the Emergency Department. There, he was
unable to give a detailed history due to confusion. On examination, he was unwell with a fever of 380C,
a tachycardia of 115, a respiratory rate of 32 and widespread crackles audible
on auscultation throughout the right upper and the left lower lobes. Arterial
blood gases showed a p02 of 50, pC02 of 35, and pH of
7.48. No sputum could be obtained for culture, but atypical serology was sent to
the laboratory. He was treated with oxygen, intravenous ceftriaxone and oral
roxithromycin, intravenous fluids and physiotherapy. He gradually recovered over
the next 3 days. Chlamydial serology was positive at a titre of 1:160, with IgM
antibodies, but no baseline serum was available. It
was only when his mental state improved that a more detailed occupational
history could be obtained. His work on the farm involved daily contact with
several hundred ducks. He would feed the ducks daily and clean out their
bedding. They lived in a large enclosed shed with an outside yard with a pond.
Several of the ducks had been ill recently and some had died. Psittacosis,
due to infection with the bacterium Chlamydia
psittaci, is a rare but important cause of pneumonia and may be transmitted
occupationally. It is usually associated with exposure to parrots, whether wild
or domesticated, but also may be transmitted from ducks, geese, chickens,
turkeys, pigeons and finches. Rarer sources of exposure are penguins and
petrels. It occurs fairly frequently in employees of duck, turkey and chicken
farms and has also been described in bird pluckers and packers. Vets, pet shop
owners and customs agents are also at risk. Treatment is with tetracycline or a
macrolide. Thus, a history of contact with birds is important not only for
diagnosing the cause of a pneumonia but for eliciting a possible compensable
disease. |