An unusual case of unilateral pulmonary edema in patients with chronic kidney disease
Article Outline
Summary
Unilateral pulmonary edema is an unusual manifestation of pulmonary edema. We report unilateral pulmonary edema in a 24-year-old man with chronic kidney disease and hypertension. He had presented with severe cough and breathlessness of short duration. Remission of pulmonary signs and symptoms along with clearance of radiologic opacities within 72
h of diuretic therapy and hemodialysis were suggestive of pulmonary edema. The exact cause of unilateral occurrence of pulmonary edema in our case could not be determined as there was no pre-existing pulmonary parenchymal or vascular abnormality.
Keywords: Unilateral pulmonary edema, Pulmonary edema, Chronic kidney disease, Hemodialysis
Introduction
Unilateral pulmonary edema is rare and may occur due to focal imbalance of Starling equation (Between hydrostatic pressure and plasma oncotic pressure) caused by abnormal pulmonary structure or other hemodynamic factors.1 Asymmetric distribution of pulmonary edema has been described. Eighteen different clinical situations were reported to have manifested with unilateral pulmonary edema, 50% of them occurring on the same side; like rapid evacuation of pleural fluid or air, prolonged lateral decubitus posture, concomitant fluid overloading and decompensated ventricular function etc.2 Unilateral pulmonary edema without pre-existing pulmonary abnormality is very rare. We report unilateral pulmonary edema in a case of chronic kidney disease.
Case report
A 24-year-old unmarried male with chronic kidney disease and hypertension presented with a history of cough and breathlessness of three days duration. He had been on regular weekly twice hemodialysis for last two months. On general physical examination, patient was having pallor and bilateral pedal edema was present. His pulse rate was 90 beats per minute, respiratory rate was 24 breaths per minute, blood pressure was 140/90mmHg and body temperature was 98.6F. Fundus examination revealed grade 3 retinopathy. Chest examination showed inspiratory crackles localized to mammary, infra axillary and infra scapular areas of right hemithorax. Cardiovascular examination revealed normal cardiac sounds and there was no murmur. Examination of other systems was unremarkable. Arterial blood gas analysis showed hypoxaemia. Blood investigations showed haemoglobin of 9.4gm%, total leucocyte count 10,000/mm3. His blood urea was 111mg%, Serum creatinine was 9.4mg%, blood sugar was 99mg%, serum Na+ 137 was mmol/L and K+ was 3.7mmol/L. A chest radiograph (Fig. 1) showed confluent alveolar opacities in the right mid and lower zones. All the sputum smears were negative. Sputum and blood cultures were negative. C- reactive protein was not elevated. Transthoracic echocardiogram showed left ventricular hypertrophy and mild mitral regurgitation. Ultrasound abdomen showed small kidneys. Intravenous frusemide, supplemental oxygen and broad range antibiotic were started, and the patient was dialyzed. His cough improved significantly and chest examination was normal within 48h of treatment. Repeat chest radiograph (Fig. 2) showed resolution of alveolar opacities on right side and the Computed tomographic (CT) of chest (Fig. 3) showed normal lung parenchyma. A diagnosis of unilateral pulmonary edema was made and antibiotic therapy was discontinued. CT angiography showed normal renal and pulmonary arteries (Figure 4, Figure 5, Figure 6, Figure 7). Patient was discharged within a week and is currently under regular dialysis in the nephrology unit.
Figure 1
A chest radiograph showing alveolar opacities on right side.
Figure 2
Repeat chest radiograph after 48
h showing resolution of alveolar opacities.
Figure 3
CT of chest showing normal parenchyma.
Figure 4
CT angiography showing normal right renal artery.
Figure 5
CT angiography showing normal left renal artery.
Figure 6
CT angiography showing normal right pulmonary artery.
Figure 7
CT angiography showing normal left pulmonary artery.
Discussion
Pulmonary edema is not rare in chronic renal failure which is usually associated with cardiovascular diseases like hypertension, left ventricular dysfunction etc.3 In renal failure, the distribution of pulmonary edema is bilateral and is usually due to excess extracellular fluid accumulation due to impaired water and solute excretion but less commonly it may occur due to increased pulmonary capillary permeability possibly enhanced by decreased plasma oncotic pressure.4 Reduction in plasma oncotic pressure is due to hypoalbuminaemia which is characteristic of chronic renal failure. In the event of associated cardiac failure, hydrostatic pressure is further increased and more fluid moves out of pulmonary capillaries. Unilateral occurrence of pulmonary edema in renal failure is rarely reported.5, 6, 7 Unilateral accumulation of fluid within the lung may manifest with abnormal radiologic appearances which are usually mistaken for an infectious cause like pneumonia or tuberculosis or occasionally alveolar haemorrhage. The exact cause of unilateral occurrence of pulmonary edema in our case is difficult to determine as there was no structural abnormality of pulmonary parenchyma or its vasculature. Based upon the short history of cough and fever, pneumonia was initially considered but rapid clinical improvement and disappearance of the alveolar opacities after diuretic treatment within 24–72h of diuretic therapy is suggestive of pulmonary edema. In our case, the cause of unilateral pulmonary edema may be due to associated cardiac dysfunction (mitral regurgitation) and in fact most cases of unilateral pulmonary edema were of cardiac origin.8 We are not aware of any situation where whole of the left hemithorax is normal and the other side still has diffuse alveolar opacities even if the pulmonary edema was initially bilateral and was partially cleared by hemodialysis. Pulmonary haemorrhage is unlikely as our patient did not undergo any invasive procedure like central venous catheter placement or needle aspiration biopsy. Any unilateral alveolar opacities in chronic renal failure, unilateral pulmonary edema should be considered in the differential diagnosis.
Conflict of interest statement
The manuscript has been approved by all the authors. None of the authors have any potential conflict of interest.
References
- Clinical and radiologic features of pulmonary edema. Radiographics. 1999;19:1507–1533
- . Unilateral pulmonary edema. Radiology. 1978;126:19–24
- . Lung disease in relation to kidney diseases. Saudi J Kidney Dis Transpl. 2005;16:282–287[serial online, cited 2008 July 4]
- . Respiratory considerations in the patient with renal failure. Respir Care. 2006;51:413–422
- . Unilateral pulmonary edema: an uncommon presentation of post streptococcal glomerulonephritis. Paediatr Emerg Care. 2003;19:337–379
- . Other causes of unilateral pulmonary edema. Am J Emerg Med. 2007;25:129–131
- . Unilateral pulmonary edema - a report of two cases. Indian J Chest Dis Allied Sci. 1992;34:157–161
- . Right upper lobe pulmonary edema caused by acute mitral regurgitation. Chest. 1993;103:1286–1288
PII: S1755-0017(08)00106-1
doi:10.1016/j.rmedc.2008.12.005
© 2008 Elsevier Ltd. All rights reserved.
