Kwashiorkor (/ˌkwɒʃiˈɔːrkɔːr, -kər/ KWOSH-ee-OR-kor, -⁠kər, is also KWASH-)[1] is a form of severe protein malnutrition characterized by edema and an enlarged liver with fatty infiltrates.

Recent studies have found that a lack of antioxidant micronutrients such as β-carotene, lycopene, other carotenoids, and vitamin C as well as the presence of aflatoxins may play a role in the development of the disease.

In at-risk populations, kwashiorkor may develop after children are weaned from breast milk and begin consuming a diet high in carbohydrates, including maize, cassava, or rice.

[7] Extreme fluid retention observed in individuals suffering from kwashiorkor is accompanied by irregularities in the lymphatic system as well as disruptions of capillary exchange.

Victims of kwashiorkor commonly exhibit reduced ability to recover fluids, immune system failure, and low lipid absorption.

[20] The low protein theory for the pathogenesis of kwashiorkor has been used to teach that capillary exchange between the lymphatic system and circulating blood is impaired by a reduced oncotic (i.e. colloid osmotic pressure, COP) in the blood, as a consequence of inadequate protein intake, so that the hydrostatic pressure gradient, which favors extravasation of fluid from small vessels, is not overcome.

The difference in the COP of the blood and tissue tends to favor the reentry of fluid from the extravascular space, into the circulatory system.

This tendency is opposed by the venous hydrostatic pressure, which tends to favor the exit of fluid from small vessels, into the interstitial space.

These include irritability, anorexia, skin desquamation, skin depigmentation, hair discoloration, reduced mitochondrial respiration, impaired lipid export from the liver without an accompanying reduction of lipoprotein synthesis, 'oxidative stress', glutathione depletions, transsulfuration disturbances, diffuse DNA hypomethylation, immune dysfunction, decreased transmethylation activity, and sulfated glycosaminoglycan deficiencies.

Aflatoxins are naturally occurring toxins produced by the mold Aspergillus flavus, a fungus found in areas with hot and humid climates.

[25][26] In particular, biological samples showed greater levels of aflatoxins in the brain, heart, kidney, liver, lungs, serum, stool, and urine.

[2] It is important to distinguish the pathophysiology of marasmus and kwashiorkor when it comes to treating malnourished children who may have hypovolemic shock that is caused by an acute loss of salt and water.

[27] It is believed to be related to high oxidant levels commonly seen in people who suffer from starvation and rarely in chronic inflammation.

[2] Glutathione serves vital functions including management of oxidative stress which is an imbalance that plays a key role in the pathogenesis of many diseases.

A proposed experimental theory suggests that alterations in the microbiome/virome contribute to edematous malnutrition, but further studies are required to understand the mechanism.

[9] Kwashiorkor is a subtype of severe acute malnutrition (SAM) characterized by bilateral peripheral pitting edema.

"[29][2][30] Additional clinical findings on physical exam include marked muscle atrophy, abdominal distension, dermatitis, and hepatomegaly.

[2][31] WHO criteria for clinical assessment of malnutrition are based on the degree of wasting (MUAC), stunting (weight-for-height Z-score), and the presence of edema (mild to severe).

[32] Because it can be difficult to measure weight-for-height Z scores (WHZ) frequently, screening is performed by physical exam, with careful examination of the child's feet to detect the presence of bilateral pitting edema.

By ensuring they are equipped with the proper education and resources, caretakers and infants are in better health, ultimately preventing childhood malnutrition.

[33] To prevent this from happening, parents can be educated on proper nutrition and the importance of breastfeeding infants to ensure they receive all the nutrients they need.

Proteins can be found in the following foods WHO guidelines outline 10 general principles for the inpatient management of severely malnourished children.

[35] Therefore, after concerns of refeeding syndrome have passed, children may require 120-140% of their estimated caloric needs to achieve catch-up growth.

Only after the primary disease is determined can an appropriate dietary plan be made, as fluid, vitamins, and macronutrients may need to be considered to not exacerbate the cause of malnutrition.

[36] Ready-to-use therapeutic foods (RUTFs) and F-75 and F-100 milks were created to provide appropriate nutrition and caloric intake to those experiencing malnutrition.

[3] A high risk of death is identified by a brachial perimeter < 11 cm or by a weight-for-age threshold < −3 z-scores below the median of the WHO child growth standards.

It is mostly observed in low-income and middle-income nations and regions such as Southeast Asia, Central America, Congo, Ethiopia, Puerto Rico, Jamaica, South Africa, and Uganda, where poverty is prominent.

"[3] Factors such as "diet, geographical locations, climate, and aflatoxin exposure" have been invoked as potential causes for observed differences in the prevalence of kwashiorkor and marasmus.

[38] Current research and recommendations to manage severe acute malnutrition (SAM), such as kwashiorkor, in children, are largely based on expert opinions.