A woman with acute dyspnoeaBMJ 2020; 368 doi: https://doi.org/10.1136/bmj.l6970 (Published 30 January 2020) Cite this as: BMJ 2020;368:l6970
- Qiaoling Zhou, nephrology ST5 registrar,
- Madhu Potluri, nephrologist consultant
- Correspondence to Q Zhou
A 60 year old woman with end stage renal disease presented with acute dyspnoea over three days.
Her end stage renal disease was secondary to diabetic nephropathy and she had been on daily automated peritoneal dialysis for more than 24 months. She had no other medical history. In the three weeks before her admission, she reported increasing leg oedema and reducing fluid removal from the automated peritoneal dialysis. She noticed that her symptoms of breathlessness worsened whenever she had the dialysates infused.
Examination revealed markedly reduced breath sounds and dull percussion over the left hemithorax.
Chest radiography (fig 1) showed a large left pleural effusion.
Results from a pleural aspiration are shown in table 1.
An echocardiogram from six weeks earlier showed normal biventricular functions.
What is the most likely cause of the pleural effusion?
A pleuroperitoneal leak (fig 1).
Pleuroperitoneal leaks occur when there are congenital or acquired communications between the pleura and peritoneum (via the diaphragm). The raised intra-abdominal pressure with dialysate infusion promotes the translocation of dialysate into the pleural space in those with or at risk of developing diaphragmatic weakness.123
In this case it was assumed that a diaphragmatic defect was acquired through gradual weakening of the diaphragm muscle fibres, resulting from long term pressure exerted by instillations of peritoneal dialysate fluid; this occurs in approximately 1-2% of people undergoing peritoneal dialysis.23
Differential diagnoses of pleural effusion in a patient on peritoneal dialysis include a pleuroperitoneal leak, fluid overload, congestive heart failure, and other causes such as underlying malignancy or parapneumonic effusion, depending on clinical context.
However, a high glucose concentration in the transudative fluid (higher than the serum glucose level) is highly suggestive of a pleuroperitoneal leak.4
In more than half the cases there is a pre-existing diaphragm defect and pleuroperitoneal leaks develop in the first month after the initiation of peritoneal dialysis.3
Risk factors for developing diaphragmatic weakness after starting peritoneal dialysis include hiatus hernia, neuromuscular disease, and Guillain-Barré syndrome.
Diaphragmatic weakness is not routinely quantitatively evaluated in clinical practice; however, according to the literature it can be evaluated through ultrasonography and/or lung function tests.5 It is not typically evident on chest radiography.
Management usually involves switching to haemodialysis; drainage is not usually required. Surgical repair of diaphragmatic defects may be required if peritoneal dialysis is to continue.6
Automated peritoneal dialysis was discontinued and haemodialysis access established. The pleural effusion resolved within a week of haemodialysis treatment, without the need for pleural drainage.
Consider a pleuroperitoneal leak when patients present with dyspnoea and a large pleural effusion while on peritoneal dialysis.
Competing interests The BMJ has judged that there are no disqualifying financial ties to commercial companies. The authors declare the following other interests: none.
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Patient consent obtained.
Provenance and peer review: not commissioned; externally peer reviewed.