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Case Study: A patient with a history of alcoholism and bilateral pneumonia

2. Patient presents to the emergency department
A 59-year-old male patient presents to the ED complaining of acute chest pain and productive cough for 24 hours
At presentation, he has moderate hypothermia (36.0°C), tachypnoea, tachycardia, SaO2 87% with FiO2 0.4 and BP 80/60 mmHg
Laboratory tests reveal:
Leukopenia (1100/mm3, mainly polymorphonuclear leukocytes [PMNs])
Anaemia (haematocrit 26.5%, haemoglobin 9.1 g/dL)
High erythrocyte sedimentation rate (ESR) (115 mm/first hour)
Chest X-rays show extensive infiltrations in the right superior and left medium lung zones
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4. History
The patient’s history reveals hospitalisation 2 years ago due to recurrent episodes of coughing and small volume hemoptysis with weight loss
He is a mariner (last sailed 6 months ago) and a habitual alcohol drinker
A chest CT scan from the previous hospitalisation demonstrates the existence of three cavitational lesions in the right lung
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5. CT scan results from the hospitalisation 2 years ago
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6. Laboratory findings and treatment 2 years ago
Persistent laboratory investigations fail to confirm a diagnosis of TB
Laboratory investigations for vasculitis and other auto-immune diseases are also negative
Despite this, he receives empiric anti-TB treatment for 1 month without clinical improvement, but there is radiological deterioration
Sputum cultures are not diagnostic and blood cultures are negative
Under the presumed diagnosis of aspiration pneumonia, he receives antimicrobial therapy with ciprofloxacin plus clindamycin, after which he has substantial clinical improvement
He is discharged from hospital, but does not return for the recommended follow-up
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7. Patient in ED: Questions
What is your differential diagnosis?
What is your opinion on the antimicrobial therapy? Which of the following would you include in a combination regimen?
Fusidic acid
Azithromycin
Fluconazole
Ampicillin/sulbactam
Piperacillin/combactam
A carbapenem
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8. Question
What is your recommendation for the patient’s therapy? Consider options other than the antimicrobial therapy
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9. Clinical course in the ED
An empiric combination therapy is commenced with:
Fusidic acid
Azithromycin
Fluconazole
Ampicillin/sulbactam
During the current hospitalisation, the patient’s condition worsens within hours, necessitating admission to the ICU. He is:
Mechanically ventilated
Transfused 1 unit of red blood cells
Microbiological investigations are performed on blood and bronchial secretions
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10. Further clinical course
He develops galactic (lactic) acidosis, hemodynamic instability, and he spikes a high fever (>39.5°C) and leukocytosis (which gradually reaches /mm3 with a predominance of PMNs)
But then his condition improves and four days later, he is discharged from the ICU as he is:
Afebrile, hemodynamically stable with normal blood gases, but with a very slight regression of his leukocytosis (20 000/mm3)
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11. Further clinical course
The next day, his fever recurs
Klebsiella pneumoniae is isolated from both blood cultures and bronchial secretions (which had been sent from the ICU) and the tip of the central vein catheter reveals presence of Acinetobacter baumannii
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12. Results of sensitivity testing
Antibiotic
K. pneumoniae*
A. baumannii
Amikacin I R
Ampicillin/sulbactam
Aztreonam
Cefepime
Ceftazidime
Ciprofloxacin
Imipenem
Meropenem S
Piperacillin/tazobactam
Tetracycline
Tobramycin
TMP/SMX
Colimycin
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*K. pneumoniae is found to produce extended-spectrum β-lactamase (ESBL) and metallo-β-lactamase (MBL)

13. Questions
The patient is again febrile. What do you think is the reason for this? e.g. consider whether treatment had failed, superinfection etc
Which antimicrobial treatment would you recommend now?
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14. Patient is transferred
Due to multiresistant infection, the patient is transferred to the Infection Unit of a tertiary care hospital
Upon admission, he is:
Febrile (38.8°C), hypoxaemic (PO2 55 mmHg), with leukocytosis (16 200/mm3) but without marked PMN (PMN 78%), ESR 105 mm/first hour, procalcitonin (PCT) ng/mL
Seriously malnourished and suffering from alcoholic polyneuritis, resulting in an inability to stand or walk
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15. Clinical course A new sputum culture is obtained
He receives combination antibiotic therapy with meropenem 1g x 3 IV and colimycin 2 MU x 3 IV and 1 MU x 3 by inhalation
Three days later, his fever is slightly reduced (~38°C), leukocytes have decreased to /mm3 and he is hemodynamically stable
A chest CT scan reveals bilateral cavitations
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16. Chest CT scan results
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17. Test results
Amplified Mycobacterium tuberculosis direct test (Gen-Probe) and Ziehl-Neelsen smear are negative
Non-quantitative sputum culture reveals presence of MRSA
Question: What is your suggestion now?
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18. Empiric therapy remains the same
The empiric regimen is not modified
Three days later, the patient is again afebrile with normal blood gases and a normal leukocyte count
During the following days, he has gradual radiological improvement
Nevertheless, he remains unable to rise from his bed; he has a coarse tremor and very severe muscle atrophy
The total duration of antimicrobial therapy is 15 days
Two days later, he is transferred to a rehabilitation centre and re-evaluation is requested after 3 months
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19. Questions Do you agree with the duration of the treatment?
What general comments would you like to make regarding this case?
How might your clinical practice be influenced as a result of this case?
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20. Comments
The infection was most likely due to the K. pneumoniae (in blood and respiratory secretions)
The organism probably developed resistance to the empiric therapy
The MRSA was likely to be a colonising organism
No antibiotic therapy was given specifically to treat infection with MRSA
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