CH WK2 CASE 3

Children’s Health – Diarrhoea and vomiting

Case Introduction – Diarrhoea and vomiting

Further Case Information – Diarrhoea and vomiting

Background Science – Diarrhoea and vomiting

Case Conclusion – Diarrhoea and vomiting

Formative Assessment – Diarrhoea and vomiting

Resources

Textbooks

· Nelson Essentials of Pediatrics:, Marcdante MD, Robert M. Kliegman MD

· Illustrated Textbook of Pediatrics 6th Lissauer (Mosby Elsevier)

Guidelines (For reading only)

· Diarrhoea and vomiting caused by gastroenteritis in under 5s: diagnosis and management

· Intravenous fluid therapy in adults in hospital

Clinical Practice Guideline: Maintenance Intravenous Fluids in Children

Guidance

Intended learning outcomes:

By the end of this case, you should be able to:

1. Formulate a differential diagnosis for a child with vomiting and/ or diarrhea

2. Recognize the clinical presentations of some common causes of vomiting and/ or diarrhea at different pediatric age groups

3. Understand the assessment of a child with vomiting and/ or diarrhea

4. Discuss the assessment of a child with a chronic diarrhea

5. Recognize red flag features which would make an organic pathology more likely in a child with chronic diarrhea

6. Apply clinical reasoning methodology to distinguish between different causes of vomiting and/ or diarrhea in children on the basis of clinical assessment.

7. Describe how to approach initial management of a child presenting with vomiting and/ or diarrhea including investigation and treatment

CASE COMPONENT

Case Introduction:

Waleed is a 7-week-old infant who presents to the emergency department (ED) with a one-week history of non-bilious vomiting. His mother describes the vomit as ‘shooting out’. He has a good appetite but has lost 300 g, since he was last weighed a week earlier. He is artificially fed taking 120 mL every 4 hours. He has mild constipation, but mother reports no changes in his urine.

The family have recently returned from a vacation abroad. There is no vomiting in any other members of the family. His sister suffers from vesicoureteric reflux (VUR) and urinary tract infections. His other older brother had similar complaints in his infancy, which resolved spontaneously as he got older. In opposite to Waleed, his brother’s symptoms started immediately after birth, but the worrying issue for the mother is that Waleed started to lose weight while his brother hadn’t. Waleed pregnancy and birth were uneventful, and he received a vaccination at birth. His metabolic newborn screening came normal.

Further case information:

On examination

Waleed vitals are Temp: 36.8; HR: 170 beats/min; blood pressure: 82/43 mmHg; RR: 20/min; and peripheral capillary refill time 3s. His togue is dry and he seems to be thirsty and drinks vigorously from his feeding bottle. There is no organomegaly, masses or

tenderness on abdominal examination. There are no signs in the other systems.

Investigations:

Normal

Hemoglobin 11.7 g/dL 10.5–13.5 g/dL

White cell count 10.0 x 109 /L 4.5–13 X 109/L

Neutrophils 7.2 x 109 /L 1.7–7.5 X 109/L

Platelets 230 X109/L 180–430 X 109/L

Sodium 134 mmol/L 135–145 mmol/L

Potassium 3.1 mmol/L 3.5–5.0 mmol/L

Chloride 81 mmol/L 98–106 mmol/L

Urea 8.0 mmol/L 1.8–6.4 mmol/L

Creatinine 40 μmol/L 18–35 μmol/L

Capillary gas

pH 7.56 7.36–7.44

PCO2 6.0 kPa 4.0–6.5 kPa

HCO3 38 mmol/L 22–29 mmol/L

Base excess +10 (−2.5)–(+2.5) mmol/L

Urine dipstick No abnormality detected

Glucose 3.2 mmol/L 3.3–5.5 mmol/L

Q1: What is the provisional diagnosis?

In an infant this age with non-bilious projectile vomiting, pyloric stenosis is the most likely diagnosis. This condition presents between 2 weeks and 5 months of age (median 6 weeks) and projectile vomiting is typical. The vomitus is never bile-stained as the obstruction is proximal to the duodenum. As in this case, infants may also be constipated.

How would you approach an infant with vomiting?

Q3: What are the most important differential diagnoses in this infant? What is with and what is against?

1. Gastro-oesophageal reflux: usually presents from or shortly after birth.

2. Gastritis: usually occurs with an enteritis and diarrhea.

3. Urinary tract infection: A urinary infection at this age may present in a very non-specific way and therefore it is mandatory to test the urine. The absence of nitrites and leucocytes in the urine dipstick makes a urinary infection very unlikely.

4. Overfeeding: should be elucidated from a careful history.

Q4: What additional examination and investigations would you like to do? How would these help you to manage the case?

Additional examination:

The diagnosis could be clinically confirmed by carrying out a test feed. A feed leads to peristalsis which occurs from left to right. The abdominal wall is usually relaxed during a feed, making palpation easier. A pyloric mass, which is the size of a 2-cm olive, may be felt in the right hypochodrium by careful palpation.

Additional investigation:

An ultrasound is also usually done for further confirmation.

Initial treatment consists of:

· Treating the dehydration, acid–base and electrolyte abnormalities with intravenous fluids (0.9 % saline with 5 % dextrose and added KCl).

· Oral feeds should be stopped, a nasogastric tube inserted and the stomach emptied.

· The definitive operation is Ramstedt’s pyloromyotomy.

The hypochloraemic alkalosis is characteristic and is due to vomiting HCl.

The low potassium is due to the kidneys retaining hydrogen ions in favour of potassium ions.

The raised urea and creatinine suggest that there is also mild dehydration.

Q5: How can the changes in blood gases, BUN and creatinine be explained?