Diarrhoea and Vomiting

Question 1

Important features in a history to assess a child with diarrhoea and vomiting:

Answer 1

Duration, frequency, volume, (any blood in the stools)

Current oral intake and usual feeding pattern

Passage of urine - no. of wet nappies, how heavy

History of fever and other red flag symptoms

Recent contact with someone with diarrhoea and vomiting, ingestion of contaminated food or water, recent travel abroad

Question 2

Physical features of dehydration in an infant

Answer 2

Sunken anterior fontanelle
Dry mucous membrane
Tachycardia
Reduced CR
Reduced skin turgor

Question 3

Most common causes of gastoenteritis

Answer 3

Rotavirus - most children under 5 will have rotavirus and develop immunity (causes gastroenteritis in 60% of children <2)

Adenovirus

Bacterial less common - Campylobacter jejuni

Question 4

Causes of blood in stool associated with D and V in children

Answer 4

Campylobacter
Rotavirus
Intussusception
E. Coli
Shigella

Question 5

What is intussusception?

Answer 5

Invagination of proximal bowel into a distal segment commonly involving invagination of ileum into caecum through the ileocecal valve.
Peak presentation is between 3 months to 2 years of age with history of paroxysmal, severe colicky pain when the child draws his/her legs up, pallor during the episodes of pain followed by recovery from the painful episodes and lethargy. The child may refuse to feed, have vomiting and pass characteristic red currant jelly stool containing blood and mucus.

Question 6

Red flags associated with vomiting

Answer 6

Blood
Bile
Projectile vomiting
Abdominal tenderness/distention
Blood in stool
Bulging fontanelle

Question 7

Common causes of vomiting in children

Answer 7

Feeding issues
GORD
Gastroenteritis

Question 8

Symptom:

Bile stained vomit

Answer 8

Possible Cause:

Intestinal obstruction

Question 9

Symptom:

Haematemesis

Answer 9

Possible Cause:

Oesophagitis
Gastric ulcer
Oral or nasal bleeding and vomiting up swallowed blood

Question 10

Symptom:

Projectile vomiting under 2 months of age

Answer 10

Possible Cause:

Pyloric stenosis

Question 11

Symptom:

Abdominal distention/tenderness

Answer 11

Possible Cause:

Intestinal obstruction
Strangulated inguinal hernia
Surgical abdomen

Question 12

Symptom:

Blood in stool

Answer 12

Possible Cause:

Gastroenetritis – salmonella or campylobacter
Intussusception

Question 13

Symptom:

Severe dehydration and shock

Answer 13

Possible Causes:

Severe gastroenteritis
Systemic infection – UTI
Meningitis
Diabetes ketoacidosis

Question 14

Symptom:

Bulging fontanelle/fits

Answer 14

Possible Cause:

Raised intracranial pressure due to meningitis/ hydrocephalus

Question 15

Symptom:

Faltering growth

Answer 15

Possible Causes:

Gastroesophageal reflux
Coeliac disease
Chronic gastrointestinal conditions

Question 16

Symptom:

Vomiting with paroxysmal cough

Answer 16

Possible Cause:

Whooping cough

Question 17

Actions to take based on leucocytes and nitrites on urine dipstick

Answer 17

Leu - neg
Nitrites - neg - UTI unlikely

Leu - pos
Nitrites - pos - suggests UTI

Leu - neg
Nitrites - pos - prelim diagnosis of UTI(and vice versa), commence Abx await culture
(most commonly E. coli)

Question 18

What is ORS?

Answer 18

Oral rehydration salts

Mix of glucose, electrolyes and salts to help the absorption of sodium via the sodium-glucose cotransporter, and in turn water is absorbed helping the body to rehydrate

Question 19

Advice for a parent of a child with gastroenteritis

Answer 19

No IV therapy necessary
Diarrhoea usually last 5-7 days
Encourage usual fluid intake
Give 5ml/kg ORS after each passage of loose stool

Wash hands after nappy change and before preparing, serving or eating food
No nursery for 48 hours after last episode

Seek help if child becomes unwell, mottled skin, vomiting (shouldnt last longer than 3 days), decreased urine output/wet nappies, irritable/lethargic and cold extremities

Question 20

Can you breastfeed during gastroenteritis?

Answer 20

Continue if tolerated

Reintroduced by 24 hours if stopped due to persistent vomiting

Usually reduces the risk of gastroenteritis, life saving in developing countries

Question 21

Properties of breast milk

Anti infective

Answer 21

Secretory IgA - provides mucosal protection

Bifidus factor - promotes growth of lactobacillus bifidus which metabolises lactose to lactic acid and acetic acid. Low pH may prevent growth of GI pathogens

Lysozyme - bacteriolytic enzyme

Lactoferrin - iron binding protein inhibits growth of E.coli

Interferon - antiviral

Question 22

Properties of breast milk

Cellular

Answer 22

Macrophages - phagocytic and synthesise lysozyme, lactoferrin, C3, C4

Lymphocytes - B cells synthesise IgA and T cells may offer delayed hypersensitivity response§

Question 23

Properties of breast milk

Nutritional

Answer 23

Easily digested protein - whey to casein ratio 60:40
Lipid (rich in Oleic acid) - easy to digest and improves fat absorption
Calcium: phosphorus 2:1 - improves calcium absorption and prevents hypocalcaemic tetany
Low renal solute load - easily digestible and fat absorption
Iron 40-50% absortion
Long chain polyunsaturated fatty acids - important for retinal development

Question 24

Viral gastroenteritis

Answer 24

Rotavirus
Enteric adenovirus 40 and 41
Calcivirus (including Norovirus)
Astrovirus

Question 25

Bacteria gastroenteritis

Answer 25

``` Campylobacter jejuni C diff E. coli Salmonella Shigella Vibrio cholerae ```

Question 26

Parasitic gastroenteritis

Answer 26

Giardia lamblia | Cryptosporidium

Question 27

Pathology of diarrhoea

Answer 27

Caused by infective or inflammatory processes in the intestine which affect the secretory or absorptive function of enterocytes

Question 28

Two primary mechanisms of infectious diarrhoea

Answer 28

Secretory | Mucosal invasion

Question 29

Effects on secretion caused by infectious diarrhoea

Answer 29

↓ absorption ↑ secretion and electrolyte transport Leads to watery stool Caused by: cholera, E.coli, C diff, cryptosporidium (HIV)

Question 30

Effects on colon due to mucosal invasion

Answer 30

Inflammation ↓ mucosal surface area and/or colonic reabsorption ↑ motility Leads to blood in stools and ↑ in WBCs Rotavirus, campylobacter, salmonella, shigella, Yersinia

Question 31

What features associated with DandV suggests a different diagnoses

Answer 31

``` Fever Tachypnoea Altered conscious level Neck stiffness Bulging fontanelle in infants Non-blanching rash Blood and /or mucus in stool Bilious vomit Severe or localised abdominal pain Abdominal distension or rebound tenderness ```

Question 32

Factors considered in assessing dehydration

Answer 32

``` Body weight (% loss) General appearance Skin turgor Tears Mucous membranes BP Urine flow Pulse Eyes Anterior fontanelle Fluid deficit ```

Question 33

Risk of dehydration increased in:

Answer 33

Children younger than 1 year, particularly under 6 months of age Low birth weight infants If more than 5 loose stools and 2 episodes of vomiting in the previous 24 hours Not offered or able to tolerate supplementary fluids before presentation Malnourished children

Question 34

Types of dehydration

Answer 34

Isonatremic – loss of sodium and water are proportional Plasma sodium remains within normal range Hyponatremic – intake of large quantity of water / hypotonic fluids, greater net loss of sodium than water, fall in serum sodium Results in shift of water from extracellular to intracellular compartment causes brain oedema and marked extracellular dehydration and shock Hypernatremic – water loss exceeds the sodium loss with resultant increase in plasma sodium concentration. This can happen when there is low sodium diarrhoea or high insensible water loss. There is shift of water from intracellular to extracellular compartment and therefore less signs of dehydration

Question 35

Features of hypernatremic dehydration

Answer 35

``` Jittery movements Increased muscle tone Hyperreflexia Convulsions Drowsiness or coma ```

Question 36

Investigations for diarrhoea

Answer 36

Stool microscopy and culture - indicated if: - Recent travel abroad - The diarrhoea is not improving by day 7 - Suspected septicaemia - Blood and /or mucus in stool Immunocompromised child Blood culture – if starting antibiotics U&E’s and glucose if dehydrated /starting intravenous fluids

Question 37

Indications for IV fluid treatment

Answer 37

Shock - fluid bolus 20ml/kg 0.9% sodium (2nd bolus if shock persists) Red flag symptoms or signs Persistent vomiting Hypoglycaemia

Question 38

What is imperative before starting IV fluids

Answer 38

Weight and U&Es should be measured at least every 24 hours Blood glucose

Question 39

Degree of dehydration

Answer 39

Mild dehydration 50 ml/kg over 4 hours Moderate dehydration 100 ml/kg over 4 hours Ongoing losses (stool) 5- 10ml/kg Reduce fluid intake when patient appears clinically hydrated Breast or formula feeding can be continued and should not be delayed for more than 24 hours

Question 40

Antibiotic treatment

Answer 40

Campylobacter – Erythromycin shortens the duration of illness and shedding of bacteria Clostridium difficile – metronidazole or vancomycin Nontyphoid salmonella, shigella , vibrio cholerae, Giardia, Yersinia and cryptosporidium

Question 41

Key differential in acute appendicitis

Answer 41

Mesenteric adenitis, especially if there was a history of sore throat

Question 42

What is Haemolytic Uraemic Syndrome?

Answer 42

Pathological Cause - E. coli 0157:H7 Triad of: Mvgticroangiopathic haemolytic anaemia Thrombocytopaenia Acute renal failure (AKI) Problem with primary haemostasis - platelet count will be low <150, bleeding time will increase Atypical in adults

Question 43

What type of anaemia is associated with HUS?

Answer 43

Normocytic anaemia Haemolytic Intravascualar Extrinsic (extra-corpuscular) Non-immune (negative Coomb's test)