From the Guidelines
Pitting edema and non-pitting edema are two distinct types of edema that differ in their underlying pathophysiology and management approaches, with pitting edema being more responsive to diuretic therapy and non-pitting edema requiring more mechanical interventions. The primary difference between pitting and non-pitting edema lies in their pathophysiological mechanisms. Pitting edema occurs due to excess fluid accumulation in the interstitial spaces, often resulting from increased hydrostatic pressure or decreased oncotic pressure, commonly seen in conditions like heart failure, kidney disease, or venous insufficiency 1. In contrast, non-pitting edema results from the accumulation of solid material in tissues, such as in lymphedema, myxedema, or lipedema.
Key Characteristics of Pitting and Non-Pitting Edema
- Pitting edema:
- Characterized by the accumulation of excess fluid in the interstitial spaces
- Often associated with conditions like heart failure, kidney disease, or venous insufficiency
- Skin indents and remains depressed temporarily when pressed with a finger
- Non-pitting edema:
- Results from the accumulation of solid material in tissues
- Often associated with conditions like lymphedema, myxedema, or lipedema
- Skin does not indent with pressure
Management Approaches
Management of pitting edema typically involves treating the underlying cause, sodium and fluid restriction, elevation of affected limbs, and diuretics such as furosemide (20-80mg daily) or hydrochlorothiazide (12.5-50mg daily) 1. In contrast, management of non-pitting edema focuses on the specific cause and often includes compression therapy, manual lymphatic drainage, and sometimes specialized treatments like complete decongestive therapy for lymphedema.
Clinical Evaluation and Diagnosis
According to the 2016 ESC guidelines for the diagnosis and treatment of acute and chronic heart failure, clinical evaluation is mandatory to select further management, and initial diagnosis of AHF should be based on a thorough history assessing symptoms, prior cardiovascular history, and potential cardiac and non-cardiac precipitants 1. The guidelines also recommend that symptoms and signs of AHF reflect fluid overload or reduced cardiac output with peripheral hypoperfusion, and careful clinical evaluation needs to be followed by additional investigations such as ECG, chest X-ray, laboratory assessment, and echocardiography.
Treatment and Therapy
In patients presenting with AHF, early initiation of appropriate therapy is of key importance, and treatment should be directed to the underlying cause of the edema, whether it be heart failure, kidney disease, or other conditions 1. The use of diuretics, such as furosemide, may be necessary to manage fluid overload, and the effectiveness of diuretics in managing edema associated with thiazolidinediones has been suggested to be variable 1.
From the Research
Pathophysiology of Pitting and Non-Pitting Edema
- Pitting edema is characterized by the accumulation of fluid in the interstitial space, which can be caused by various factors such as venous insufficiency, systemic disease, or congestive heart failure 2, 3.
- Non-pitting edema, on the other hand, is often associated with lymphedema, which is characterized by the accumulation of protein-rich fluid in the interstitial space due to lymphatic insufficiency 2, 4.
Clinical Characteristics of Pitting and Non-Pitting Edema
- Pitting edema is typically soft and indentable, with a noticeable reduction in swelling after elevation of the affected limb 5.
- Non-pitting edema, also known as brawny edema, is characterized by a hard, non-indentable texture, often with a thickened skin and decreased mobility of the affected limb 2, 5.
Management of Pitting and Non-Pitting Edema
- The management of pitting edema often involves the use of diuretics, such as furosemide, to reduce fluid accumulation, as well as compression stockings and elevation of the affected limb to improve lymphatic drainage 3, 6.
- The management of non-pitting edema, such as lymphedema, typically involves the use of compression devices or stockings, as well as skin care and exercise to improve lymphatic function 2, 5.
Diagnosis and Assessment of Pitting and Non-Pitting Edema
- The diagnosis of pitting and non-pitting edema often involves a combination of clinical assessment, including the pitting test, and imaging studies, such as duplex ultrasonography or magnetic resonance venography 2, 5.
- The pitting test, which involves applying sustained pressure to the affected area, can help differentiate between pitting and non-pitting edema, although the test is not standardized and requires further evaluation 5.