The use of Renastep™ as part of the dietary management of Acute Kidney Injury (AKI) | Case Study

Age:16 years

Gender: Female

Diagnosis: 
Acute Kidney Injury (AKI) with hypercalcaemia. Background of Trisomy 21 and oral aversion.

Relevant History: 
Patient was admitted following routine blood tests having been found to be in AKI. At the time of admission it was unknown if there was a background of Chronic Kidney Disease (CKD) or evolving AKI with unknown cause. The patient was given IV fluids, with serum and urinary investigations. 

Anthropometry:

• Weight on admission: 27.3kg <0.4th centile* 
• Current weight: 36.7kg 2nd centile*
• Height on admission: 128cm 0.4th centiles*
• Current height: 131.2cm 0.4th-2nd centile*

Feeding history:
Only managing porridge with milk and the occasional yogurt at school. Fluid intake is poor.

Plan: 
Meet energy and protein requirements whilst managing potassium and phosphate intake by reducing the patients intake of cow’s milk and using Renastep and a juice based oral nutritional supplement (ONS) instead.

Nutritional Requirements: 
EAR based on weight on admission = 1201kcal/day
EAR based on ideal body weight of 55.3kg = 2430 kcals/day

Protein: 45.4g/day 
12-20 mmol Ca/day
 

The patient was regularly reviewed in clinic; she was keen to take more porridge at home and had started taking yogurts at school. Her kidney function was improving; her serum potassium and phosphate levels had normalised. Her family were making 5 bowls of porridge per day for her; 3 bowls made with 125mls of Renastep per bowl, 1 with juice-based ONS, and 1 with cow’s milk.

Estimated Dietary Intake: 1398kcal, 38g protein, potassium 117mmol, phosphate 11.3mmol, calcium 19.5mmol.

It was felt that the patient could eat more so the family were advised to make any additional bowls of porridge with a non-calcium-fortified plant-based milk alternative. 

Six months after admission: 

• Once the patients serum potassium and phosphate levels normalised, Renastep was discontinued.
• Cow’s milk and yogurts have been increased to meet LRNI for calcium. 
• Non-calcium fortified plant-based milk alternatives continue.

Estimated Dietary Intake: 1590kcal, 51g protein, 25.4mmol potassium, 22mmol phosphate, 22mmol calcium

• The use of Renastep enabled a reduction in potassium and phosphate intake which meant the patients serum potassium and phosphate levels returned to be within the reference range. 
• Renastep is 2kcal/ml which resulted in energy and protein being provided whilst limiting potassium and phosphate intake – this was an ideal way to provide nutrition support for this patient. 
• Renastep can be taken as a drink, added to foods or used in recipes. .
• Renastep is convenient and easy to use.