Diagnosing cow's milk protein allergy

Cow’s milk protein allergy (CMPA) presents with diverse and often non-specific signs and symptoms, resulting in frequent misdiagnosis or a delay in diagnosis. Guidelines and tools are available to support an early diagnosis of CMPA.

CoMiSS® awareness tool

Leading experts have developed the Cow’s Milk-related Symptom Score (CoMiSS®)1, which is a fast and easy-to-use tool to help healthcare professionals recognize and assess non-specific signs and symptoms that could be indicative of CMPA as early as possible.
Find out more about CoMiSS®

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CoMiSS® tutorial video

Discover how easy it is to use CoMiSS® to assess and interpret the severity of non-specific signs and symptoms that may be related to CMPA, such as crying, regurgitation, diarrhea or constipation, skin and respiratory symptoms.

Watch the CoMiSS® tutorial video

CoMiSS® awareness tool

If you suspect your patient is suffering from symptoms that may be suggestive of CMPA, use the CoMiSS® tool to score and assess the likelihood of CMPA.

Start scoring
Diagnosing CMPA

Your steps on the diagnosis path

The overall goal is to shorten the diagnosis process and reduce the patient burden. Achieving this goal involves multiple steps: checking the infant’s symptoms and family history; performing diagnostic tests; and confirming the diagnosis with an elimination diet followed by food challenge.

Step 1
Check symptoms and family history

The first step is to check for signs and symptoms that could be related to CMPA. It is also important to collect the family history for atopic diseases, as the risk for allergies is higher in families with existing allergic disease.

Signs & symptoms CoMiSS® tool
Step 2
Proceed to diagnosis

Available diagnostic methods

Few procedures exist to detect different types of CMPA; however, none of these tests, except for the elimination diet followed by food challenge, can provide a conclusive diagnosis. The elimination diet followed by food challenge is recommended by guidelines as the gold standard diagnostic test.2,3

Step 3
Confirm your diagnosis

Elimination diet and food challenge

The elimination diet consists of the elimination of cow’s milk protein (CMP) from the infant’s diet (which means eliminating CMP from the mother’s diet in case of breast feeding).

If elimination of the CMP from the infant’s diet does not improve symptoms, CMPA is highly unlikely. If symptoms improve, an oral food challenge is usually performed by controlled re-introduction of CMP to confirm the diagnosis of CMPA.4,5

When CMPA has been confirmed, a therapeutic elimination diet free from CMP will be required.

Guidelines for diagnosis and management

More detailed information about the diagnosis and management of CMPA can be found in the European Society of Paediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN) and in the European Academy of Allergy and Clinical Immunology (EAACI) guidelines.2,4

Read the ESPGHAN Guidelines
Read the EAACI Guidelines

Expert corner: CMPA diagnosis

Watch leading experts sharing their experience in diagnosing CMPA, including investigating the likelihood of CMPA with the CoMiSS® tool, the available allergy tests, and confirming the diagnosis with an elimination diet followed by oral food challenge.


  1. Vandenplas Y, et al. A workshop report on the development of the Cow’s Milk-related Symptom Score awareness tool for young children. Acta Paediatr. 2015;104(4):334–9.
  2. Koletzko S, et al. Diagnostic approach and management of cow’s-milk protein allergy in infants and children: ESPGHAN GI Committee practical guidelines. J Pediatr Gastroenterol Nutr. 2012;55(2):221–9.
  3. Luyt D, et al. BSACI guideline for the diagnosis and management of cow’s milk allergy. Clin Exp Allergy. 2014;44(5):642–72.
  4. Muraro A, et al. EAACI Food Allergy and Anaphylaxis Guidelines: diagnosis and management of food allergy. Allergy. 2014;69:1008–25.
  5. Vandenplas Y, et al. Guidelines for the diagnosis and management of cow’s milk protein allergy in infants. Arch Dis Child. 2007;92:902–8.
IMPORTANT NOTICE: Mothers should be encouraged to continue breastfeeding even when their babies have cow’s milk protein allergy. This usually requires qualified dietary counseling to completely exclude all sources of cow’s milk protein from the mothers’ diet. If a decision to use a special formula intended for infants is taken, it is important to follow the instructions on the label. Unboiled water, unboiled bottles or incorrect dilution can make babies ill. Incorrect storage, handling, preparation and feeding can eventually lead to adverse effects on the health of babies. Formula for special medical purposes intended for infants must be used under medical supervision.