Is there ascites in marasmus and how does it differ from Kwashiorkor?

November 14, 2025 •

2 min read

According to the World Health Organization, millions of children under five suffer from severe acute malnutrition, with marasmus and kwashiorkor being the two primary clinical forms. Ascites, the accumulation of fluid in the abdominal cavity, is a hallmark feature of kwashiorkor, but is generally absent in uncomplicated marasmus.

Quick Summary

This article explores the distinct mechanisms of fluid retention in different types of severe acute malnutrition. It details why ascites is characteristic of Kwashiorkor due to protein deficiency and low albumin, while the general lack of edema is a key feature of pure marasmus. The content also addresses the complexities of the mixed marasmic-kwashiorkor diagnosis.

Key Points

No Ascites in Pure Marasmus: Uncomplicated marasmus is defined by the absence of edema and ascites, unlike kwashiorkor.
Kwashiorkor's Key Feature: The primary cause of ascites in kwashiorkor is severe protein deficiency, leading to low blood albumin (hypoalbuminemia) and fluid leakage.
Marasmic-Kwashiorkor Combination: A mixed form of malnutrition, marasmic-kwashiorkor, involves both extreme wasting (from calorie and protein lack) and edema, which can include ascites.
Different Nutritional Deficiencies: Marasmus results from a deficit of all macronutrients, causing the body to consume its own tissues, while kwashiorkor is characterized by a disproportionately low protein intake.
Critical Diagnostic Distinction: The presence or absence of edema is a crucial clinical sign for healthcare providers to differentiate between the primary types of severe acute malnutrition and guide appropriate treatment.
Different Physiological Adaptations: The body's adaptive response to starvation in marasmus does not result in the severe hypoalbuminemia and hormonal shifts that lead to edema in kwashiorkor.

Understanding Severe Acute Malnutrition

Severe Acute Malnutrition (SAM), often referred to as protein-energy malnutrition (PEM), affects millions globally. Marasmus and kwashiorkor are the main severe forms, differing significantly in presentation and pathophysiology, particularly regarding fluid retention and ascites.

The Pathophysiology of Marasmus

Marasmus results from prolonged severe calorie and protein deficiency, leading to muscle and fat loss. This 'wasting' condition, named from the Greek for 'wasting,' shows as severe emaciation without swelling. The body conserves energy, but insufficient protein doesn't cause the severe low albumin (hypoalbuminemia) seen in kwashiorkor, thus maintaining fluid balance and preventing edema and ascites.

The Pathophysiology of Kwashiorkor and Edema

Kwashiorkor, primarily a protein deficiency with adequate calories, leads to low albumin. Low albumin disrupts fluid balance by reducing oncotic pressure in blood vessels, causing fluid to leak into tissues. This results in characteristic edema, ascites, and facial swelling.

The Mixed Syndrome: Marasmic-Kwashiorkor

When symptoms of both marasmus and kwashiorkor are present, it's diagnosed as marasmic-kwashiorkor. This mixed form includes both severe wasting and edema, often with ascites, due to a combined deficiency of calories and protein.

Comparison of Marasmus and Kwashiorkor

A table highlighting key differences:


Feature	Marasmus	Kwashiorkor	Marasmic-Kwashiorkor
Dietary Deficiency	Severe lack of both calories and protein.	Primary lack of protein, with adequate or near-adequate calories.	Severe lack of both calories and protein.
Physical Appearance	Emaciated, wasted, 'old man' face, loose skin folds.	Puffy, swollen appearance, with distended abdomen and edema.	Combination of emaciation and edema.
Muscle Wasting	Severe and visible.	Less visible due to edema, but still present.	Present and often severe.
Subcutaneous Fat	Markedly depleted.	Retained or less severely depleted than in marasmus.	Depleted.
Edema/Ascites	Typically absent.	Characteristic and prominent feature.	Present.
Hypoalbuminemia	Moderate, less pronounced.	Severe.	Varies, but contributes to edema.
Onset	Usually in infants under one year old.	Usually in children over one year old, often after weaning.	Can occur at various ages.

Treatment Implications

Different clinical signs require distinct treatment approaches. Both marasmus and kwashiorkor need careful nutritional rehabilitation to avoid refeeding syndrome. However, edema and ascites in kwashiorkor require specific fluid and electrolyte management. WHO guidelines offer specific refeeding protocols, distinguishing edematous malnutrition (kwashiorkor). For more details on the physiological differences, a comprehensive review can be found on the National Institutes of Health website. [https://www.ncbi.nlm.nih.gov/books/NBK559224/]

Conclusion

Pure marasmus is not characterized by ascites. This absence of fluid is a key distinction from kwashiorkor, which is defined by edema and potential ascites due to severe hypoalbuminemia. The presence of both severe wasting and edema, including ascites, indicates the mixed marasmic-kwashiorkor condition. Accurate diagnosis based on these presentations is vital for appropriate nutritional and medical interventions. Effective management, especially with edema and ascites, requires a targeted approach addressing caloric and protein deficiencies, and critical fluid and electrolyte imbalances.

Frequently Asked Questions

The main difference is the presence of edema and ascites. Kwashiorkor features fluid retention and a swollen appearance due to severe protein deficiency, while marasmus is defined by severe wasting and emaciation from overall caloric and protein deprivation.

Ascites in kwashiorkor is caused by severe hypoalbuminemia, where low levels of the blood protein albumin cause a drop in oncotic pressure, leading to fluid leaking into body tissues. In marasmus, although there is protein deficiency, it is not as pronounced as the overall caloric deficit, so severe hypoalbuminemia and subsequent edema are not typical.

Yes, a mixed form of severe malnutrition known as marasmic-kwashiorkor is possible. This is diagnosed when a patient presents with both the extreme wasting characteristic of marasmus and the edema and ascites associated with kwashiorkor.

The presence or absence of edema, including ascites, is a primary diagnostic marker used to differentiate between classic kwashiorkor and marasmus. It helps clinicians understand the underlying physiological derangements, but the existence of the mixed form means it's not the only factor.

The 'old man' or 'wizened' face is a classic sign of marasmus, resulting from the severe loss of subcutaneous fat from the cheeks.

Marasmus typically affects infants under one year old who are deprived of adequate calories and protein. Kwashiorkor is more common in children over one year of age, often after weaning, when their diet shifts to starchy foods with insufficient protein.

A diet low in protein but high in carbohydrates is a known factor in kwashiorkor, exacerbating the low albumin levels that cause edema. The general caloric and protein starvation of marasmus does not create the same fluid imbalance, which is a key physiological difference.