European Journal of Cardiovascular Medicine

Pleural effusion is a common clinical problem encountered in both inpatient and outpatient settings and usually presents with symptoms such as progressive shortness of breath, cough, chest pain, or chest heaviness. The severity of symptoms depends on the volume of fluid, the rate of accumulation, and the underlying lung and cardiac reserve of the patient. Small effusions may be asymptomatic and detected incidentally, whereas large or rapidly accumulating effusions can cause significant respiratory distress.¹ A careful clinical and radiological evaluation is therefore central to identifying the likely etiology and guiding further management.Clinical evaluation begins with a detailed history focusing on the onset and progression of symptoms, associated fever, weight loss, chest pain, hemoptysis, or orthopnea. Past history of cardiac disease, malignancy, tuberculosis, recent pneumonia, trauma, surgery, or thromboembolic disease provides important diagnostic clues². Drug history, occupational exposure, and smoking history are also relevant. On physical examination, classical findings include reduced chest expansion on the affected side, stony dullness to percussion, diminished or absent breath sounds, and reduced vocal fremitus. Large effusions may cause mediastinal shift and tracheal deviation to the opposite side³. Features such as fever, toxicity, or pleuritic chest pain suggest infective causes, while signs of heart failure or malignancy may point toward systemic disease.Radiological evaluation plays a pivotal role in confirming the presence of pleural effusion, assessing its size, and identifying associated lung or mediastinal pathology. Chest radiography is usually the first investigation. On an erect posteroanterior view, blunting of the costophrenic angle is the earliest sign, typically seen when more than 200 mL of fluid is present⁴. Larger effusions produce a homogeneous opacity with a concave upper border (meniscus sign). Lateral decubitus views help differentiate free-flowing from loculated effusions and can detect smaller volumes of fluid.⁵Thoracic ultrasonography has become an essential bedside tool for evaluating pleural effusions. It is more sensitive than chest radiography and can detect minimal fluid collections. Ultrasound helps in quantifying the volume, determining whether the effusion is free or loculated, and identifying internal septations or pleural thickening⁶. These features are particularly useful in parapneumonic and tuberculous effusions, which are common in countries such as India, in contrast to the United Kingdom and United States, where cardiac failure and malignancy predominate⁷. Ultrasound also improves the safety and accuracy of pleural interventions.Computed tomography of the chest provides detailed anatomical information and is especially valuable when the underlying cause is unclear. CT can identify pleural thickening, nodularity, loculations, lung masses, lymphadenopathy, and pulmonary embolism, and can differentiate pleural from parenchymal disease.^8,9 Contrast-enhanced CT is particularly helpful in suspected malignancy or complicated infections.

AIM

To evaluate the clinical profile and radiological features of pleural effusion in affected patients.

The present study was conducted in the Department of Medicine at S.P. Medical College and P.B.M. Associated Group of Hospitals, Bikaner. It was designed as a cross-sectional, hospital-based study carried out at a tertiary care centre. The study population comprised patients admitted to the medicine wards in whom pleural effusion was detected either on routine clinical examination or during radiological

A total of one hundred consecutive patients with pleural effusion who provided informed consent and agreed to undergo detailed clinical, radiological  evaluation were included in the study. Adult patients aged more than 18 years with pleural effusion diagnosed clinically and/or radiologically were eligible for inclusion. Patients who were unwilling to participate or did not give informed consent were excluded from the study.

Table 1: Distribution of cases according to age group (years)

In the present study of 100 cases, bilateral pleural effusion was the most common (53%), followed by right-sided (26%) and left-sided effusions (21%), with varied age distribution across all groups. The mean age did not differ significantly between right, left, and bilateral pleural effusions, and the difference was statistically insignificant (p > 0.05).

Table 2: Distribution of cases according to chief complaints

In the present study, breathlessness (52%) was the most common presenting complaint, followed by fever (48%), with a higher frequency observed in patients with bilateral pleural effusion, while cough, chest pain, abdominal pain, decreased urine output, jaundice, dysphagia, and abdominal swelling were less common. Statistical analysis showed no significant difference among most symptoms (p > 0.05), except chest pain and decreased urine output, which were significantly associated with the type of pleural effusion (p < 0.05).

Table 3: Distribution of cases according to systolic blood pressure (mmHg)

Most patients had systolic blood pressure within the normal range, although elevated systolic BP (>140 mmHg) was noted in a small number of cases, predominantly in the bilateral pleural effusion group. The mean systolic blood pressure differed significantly among right, left, and bilateral pleural effusion groups, with the highest values observed in bilateral effusions (p < 0.01).

Table 4: Distribution of cases according to diastolic blood pressure (mmHg)

Most patients had diastolic blood pressure within normal limits, with no cases of diastolic BP >90 mmHg in right- or left-sided pleural effusion groups and only three cases in the bilateral group. The mean diastolic BP was significantly higher in patients with bilateral pleural effusion compared to unilateral effusions, and the difference was statistically significant (p < 0.01).

Table 5: Distribution of cases according to Hemoglobin (mg/dl)

Across all groups, patients showed a wide distribution of hemoglobin levels, with the majority having values above 9 g/dL, and the highest proportion of hemoglobin >11 g/dL seen in the bilateral pleural effusion group. The mean hemoglobin levels did not differ significantly between right-sided, left-sided, and bilateral pleural effusions, and the difference was statistically insignificant (p > 0.05).

Table 6: Distribution of cases according to RBC (cumm)

Most patients had RBC counts either below 4 or within the 4–11 range, with no cases having RBC counts above 11,000, and lower values were more frequent in left-sided and bilateral pleural effusion groups. The mean RBC count differed significantly among the groups, being lowest in left-sided pleural effusion, and this difference was statistically significant (p < 0.05).

Table 7: Distribution of cases according to CT Findings

According to CT scan findings, in 6 cases bilateral pleural effusion and 4 cases had left sided pleural effusion. Out of 6 bilateral cases and 3 cases had cholelithiasis and 1 case had silico tuberculosis and the difference was found statistically insignificant (p>0.05).

Table 8: Distribution of cases according to final diagnosis

Tubercular pleural effusion was the most common diagnosis (36%), predominantly presenting as unilateral effusions, followed by dengue fever (20%) which showed a higher association with bilateral pleural effusion, while CKD and CLD accounted for 11% cases each. Comparative analysis showed a significant association of CLD, tubercular pleural effusion, CKD, severe anaemia, and malignant pleural effusion with the type of pleural effusion (p < 0.05), whereas synpneumonic effusion, nephrotic syndrome, acute pancreatitis, dengue fever, and CHF were not significantly associated (p > 0.05).

Present study was conducted in the Department of Medicine, S.P. Medical College and P.B.M. Associated Group of Hospitals, Bikaner. One hundred consecutive cases were selected during the period of 4 months from September 2020 to December 2020.

In present study, the prevalence of pleural effusion hospitalized patients in medicine wards is 1.92%.

In the present study, the patients are in the age range from 18 to 92 years and the incidence of pleural effusion was maximum (35%) in the age group 21-40 years.Study conducted by Sharma & Mohan¹⁰ also found that age ranging between 15 to >61. Maikap et al¹¹ showed that tubercular pleural effusion was maximum in the age group 21-30 years.

In present study, most common chief complaint was breathlessness where total 52 patients were found and out of them 13, 8 and 31 cases belonged to right sided, left sided and bilateral pleural effusion groups respectively followed by fever where total 48 cases were found and out of them 13, 11 and 24 cases were right sided, left sided and bilateral pleural effusion group respectively, cough was present in 17 cases and out of them 2, 7 and 8 cases belonged to right sided, left sided and bilateral pleural effusion group respectively, 12 cases each had chest pain, pain abdomen and decrease urine output while 5 cases had jaundice while least common chief complaint was dysphasia and abdominal swelling where 4 cases each were found.A study done by Singh et al¹² observed that the most common symptom was breathlessness (51.5%), followed by fever (39%), chest pain (38.5%), cough (35%), and weight loss (30%).

In the present study, the majority of cases had their systolic BP within normal range while 2, 1 and 10 cases of right sided, left sided and bilateral pleural effusion group had their systolic blood pressure >140mmHg. This difference was found statistically significant (p<0.01).

In the present study, no patient in the right sided and left sided group had their diastolic BP >90mmHg while in the bilateral group only 3 patients had their diastolic BP >90mmHg.  This difference was found statistically significant (p<0.01).

According to CT scan findings, in 6 cases bilateral pleural effusion and 4 cases had left sided pleural effusion. Out of 6 bilateral cases and 3 cases had cholelithiasis and 1 case had silico tuberculosis (p>0.05).

In present study, most common diagnosis tubercular pleural effusion where total 36 cases were found and out of them 17, 12 and 7 cases belonged to right sided, left sided and bilateral pleural effusion groups respectively, followed by dengue fever where total 20 cases were found and out of them 6, 2 and 12 cases belonged to right, left and bilateral pleural effusion groups respectively, chronic kidney disease and chronic liver disease was found in 11 cases each, while 4 patients each had syn pneumonic effusion, nephritic syndrome and malignant pleural effusion while 7 patients had acute pancreatitis, 3 patients had CHF and 2 cases had severe anaemia.

Syn Pneumonic effusion, nephritic syndrome, acute pancreatitis, dengue fever, congestive heart failure had an insignificant difference (p>0.05 in all) when compared in pleural effusion groups while chronic liver disease, Tubercular pleural effusion, chronic kidney disease, severe anaemia and malignant pleural effusion had a significant difference (p<0.05 in all).

Two cases had mixed diagnosis and out of them 1 had chronic live disease with severe anaemia and another had chronic kidney disease with severe anaemia.

The present study concluded that the etiological diagnosis of pleural effusion remains unchanged even after a few decades in our country. Despite the revised National tuberculosis control programme in India the tubercular effusions are still in large numbers, the cause is usually the non compliance with anti-tubercular therapy. In our study, the second most common cause is dengue fever which was uncommon in previous studies. This may be due to an outbreak of dengue fever during the present study period. The malignant pleural effusion cases are far less than tuberculosis, but their incidence is rising as compared to previous studies. Other causes include chronic liver disease, chronic kidney disease, acute pancreatitis, Syn pneumonic effusion etc. While evaluating a case of pleural effusion, combined approach, involving clinical evaluation, radiographic and sonographic evaluation, pleural fluid analysis and in cases where possible thoracoscopic pleural biopsy, must be utilized for fruitful and accurate diagnosis.

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