Pleural effusion (PE) is an abnormal collection of fluid in the pleural space. The etiological spectrum of pleural effusion depends on the geographical region and the local incidence of different diseases that cause pleural effusions. In the developed countries, the common causes of pleural effusion in adult are cardiac failure, malignancy and pneumonia .¹ Whereas, in developing countries tuberculosis and par pneumonic effusions are more. ^2,3

Pleural effusion is a common finding among patients presenting with cardiopulmonary symptoms. A systemic approach to the investigations is needed due to the extensive differential diagnosis. Pleural effusions can be transudative or exudative.⁴ In cases with transudative pleural effusion, the diagnosis is usually made without much difficulties, but exudative pleural effusion requires careful differential diagnosis that includes parapneumonic effusion, tuberculosis (TB), and

metastatic cancers which are found to be the cases in large number of patients^.

If metastatic cancer leads to hypoalbuminemia (e.g., due to liver metastasis causing liver failure or nephrotic syndrome), it may cause transudative effusion due to decreased oncotic pressure.

Light's criteria are frequently used to distinguish between exudative effusion and transudative effusion, the two types of pleural effusions.¹ If any one of the following conditions is met, the pleural fluid is exudative: pleural fluid protein/serum protein ratio >0.5; pleural fluid lactate dehydrogenase/serum LDH ratio >0.6; or pleural fluid LDH level >2/3 the upper limit.

Prospective study was conducted in the department of General medicine at TRR medical college for duration of 1 year i.e. from March 2021 to Feb 2022. Ethical permission was taken from Institutional ethical committee. Written consent was obtained from all the study participants

Sample size: 65

Inclusion criteria

• Age 10-60 years
• Patients with clinically or radiologically documented pleural effusion.

Exclusion criteria

• Age <10 years and more than 60 years
• Patients with hydropneumothorax and trauma chest
• Past history of thoracocentesis

Methodology

The demographic data collected included age, sex, and address.  A detailed history was obtained inlcuding  chief complaints, history of presenting illness, and significant history including the drug history. A through physical examination was done. Investigations such as complete hemogram, random blood sugar, renal function tests, serum albumin, chest-X-ray, and pleural fluid analysis and cytology were carried out in all the cases.

Pleural fluid analysis on neubar chamber: Total Leucocyte Count

LIGHT et al.’s ^criteria were used to distinguish exudative from transudative effusions. Predominant pleural fluid cell types were defined based on British Thoracic Society guidelines.

Pleural fluid cytology

The International System (TIS) for reporting serous fluid cytopathology was proposed by the International Academy of Cytology and the American Society of Cytopathology.^6,

Table 1:Diagnostic categories of TIS for reporting serous effusion cytopathology⁸

Table 1: Age distribution

In the present study age distribution varied from 10 - 60 years . Majority noted among 41-50 years constituting 43% (28/65)  and 23% (15/65) among 31-40 years , 15.3%(10/65) among 21-30 years and 51-60 years .3.0% (2/65).

Females were predominant constituting  69.2% (45/65) and Males accounting 30.7%(20/65).

Fever  was predominant symptom constituting  92.3% (60/65) ,followed  by cough 76.9% (50/65), Breathlessness 69.2% (45/65), and chest pain 61.5%(40/65).

 Right side 76.9%(50/65) was more common compared to Left side 23.0%(15/65)

Hypertension  and Coronary artery disease  constituting  33.8%(22/65) and 32.3%(21/65). Diabetes mellitus  16.9%(11/65),Rheumatoid arthritis  9.2% (6/65) and  Pancreatitis 9.2% (6/65).

Table-2: Distribution of Nature of effusion

In the present study Exudative  61.5%(40/65) and Transudative  38.4%(25/65). Purulent 76.8%( 50/65) , Hemorrhagic  15.3%(10/65) and Straw colored 7.6%(5/65) .

Table-3:  Distribution of Clinical diagnosis

In the present study Tb was commonly reported accounting 38.4%(25/65) , Pneumonia  30.7% ( 20/65), Empyema , Pancreatitis ,Liver cirrhosis and Malignancy 7.6%(5/65)

Figure-1:  Bar diagram showing Distribution of Clinical diagnosis

Table-4: DLC  on Nuebar chamber

In our study lymphocytes mean was 42.9+10.3 and Nuetrophils58.3+20.9

Table-5: Distribution of Cytological diagnosis

In our study No malignant cells noted in 92.4% cases and Malignant cells seen. In 7.6% cases.

In the present study age distribution varied from 10 - 60 years . Majority noted among 41-50 years constituting 43% (28/65)  and 23% (15/65) among 31-40 years , 15.3%(10/65) among 21-30 years and 51-60 years .3.0% (2/65).In Shashikanth et al⁹  study  mean age was 38.10 years. In Saurabh et al¹⁰  study mean age was 53.32 ± 9.15 years.

In the present study Females were predominant constituting  69.2% (45/65) and Males accounting 30.7%(20/65).Where as in Saurabh et al ¹⁰, Arif et al¹¹  and Shashikanth et al study⁹  with Male gender were more common with (67.86%) , (66.9%) and 70 (70%).

In the present study Right side 76.9%(50/65) was more common compared to Left side 23.0%(15/65)/.Similar findings were noted with  Arif et al ¹¹.Saurabh  al¹⁰  and Shashikanth et al⁹  study 46.9% ,58.93% and 41.07%.

In the present study Chest pain  was predominant symptom Fever constituting  92.3% (60/65) ,followed by cough 76.9% (50/65), Breathlessness 69.2% (45/65), Fever 61.5%(40/65). In Arif et al¹¹ study  majority of pleural patients presented with chest pain (78.5%) followed by cough (50.7%), fever (46.1%) and breathlessness (32.2%).In Shashikanth et al⁹ study  fever (53%) and breathlessness (45%) were most common symptoms, followed by, cough, chest pain, and abdominal pain .In Ranganathan et al¹² study fever and cough are the most common seen 64 and 76 percentage respectively, followed by chest pain (44) and breathlessness (42%).In Saurabh et al  ¹¹ study cough (78.57%), chest pain (67.86%), decreased appetite (64.29%), fever (62.50%), breathlessness (58.93%), weight loss (21.43%) and joint pain (16.07%).

In the present study Tb was commonly reported accounting 38.4%(25/65) , Pneumonia  30.7% ( 20/65), Empyema , Pancreatitis ,Liver cirrhosis and Malignancy 7.6%(5/65). In Souruabh et al¹⁰ study Tuberculosis (58.93%) was most common cause of exudative pleural effusion followed by empyema (8.93%), malignant (5.36%), pancreatitis (5.36%), rheumatic arthritis (3.57%) and para pneumonic (1.79%). Undiagnosed cases were 16.07%.In Arif et al¹¹  study tuberculosis (64.6%) was the most common followed by  Para pneumonic (14.6% and malignancy (11.5%)

In the present study Exudative 61.5%(40/65) and Transudative 38.4%(25/65). .Similar findings were noted with  Arif et al ¹¹ and Shashikanth et al ⁹ study with 90.8% and 66% .

In the present study Purulent 76.8%( 50/65) , Hemorrhagic  15.3%(10/65) and Straw colored 7.6%(5/65). In Souraubh et al¹⁰ study pleural fluid Appearance was Straw colored (55.36 %) in majority cases and purulent in 5 cases .only (8.93 %). In Ranganathan et al¹² study majority of the patients with tuberculous pleural had yellowish and turbid fluid, while malignant pleural effusion had hemorrhagic fluid.

In our study Predominant Neutrophilia  seen in 46.1% cases where as in Ranganathan et al^12, Souraubh et al¹⁰ study  and Kaushal et al study¹¹³ shows predominant lymphocytosis .

Etiological evaluation of pleural effusion is very important for management of the disease. Among patients of exudative pleural effusion male gender, right sided effusion, tuberculosis, straw coloured pleural fluid, raised TLC were common findings. Knowledge of the etiological pattern of exudative pleural effusion helps

physicians to plan diagnostic tests, and to provide appropriate treatment to reduce mortality and morbidity rates resulting from Plueral effusion  complication .

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