GI: diarrhea and malaria

Types of diarrhea

Acute watery diarrhoea: Diarrhoea that lasts less than 14 days.

• Dysentery: Diarrhea with visible blood in the faeces.

• Persistent diarrhea: Diarrhoea that begins acutely, but is of unusually long duration; lasting 14 days or more. It may begin as watery diarrhoea or as dysentery

Chronic diarrhoea, which is sometimes used interchangeably with persistent diarrhoea, actually refers to long-lasting (≥14 days) or recurrent diarrhoea that is not associated with an infectious cause.

Cholera: copious diarrhea and severe vomiting

Mechanisms of watery diarrhea

Secretion:It is characterized by abnormal secretion of fluid and electrolytes into the small bowel

Osmosis: When a poorly absorbed, osmotically active substance is ingested, water moves from the ECF into the bowel, thus increasing stool volume and causing dehydration.

Assessment of dehydration

Mild: <5% infants <3% older children

Moderate: 5-10%, 3-6%

Severe: >10%, >6%

Problems associated with diarrhea

Malnutrition

• Fever

• Vomiting

• Excessive weakness • Rash

• Convulsion

• Sepsis

Treatment of no signs of dehydration

50-100 ml of ORS or SSS given after each loose stool if <2yrs, and 100-200mls if >2yrs.

Treatment of some Dehydration

Diarrhoea Treatment Unit’ (DTU) or ‘ORT corner’ of the health care facility. After being re-assessed to be improving, treatment can be continued at home.

75mls/kg of ORS over 4 hours.

Severe dehydration treatment

intravenous rehydration. 100mls/kg of IV fluid should be given over a total of 3 hours (for older children) or 6 hours (for infants).

30ml/kg over one hour, followed by 70ml/kg over the next 5 hours.

• For older children, 30ml/kg over 30 mins, followed by 70ml/kg over the next 2.5 hours

Preferred fluids

Maximum rate for ng tube and why?

When do you not give ors?

Ringers Lactate/Hartmann’s

Normal saline

Half strength Darrows

Note: dont give dextrose water only!

In exceptional cases where IV therapy is not possible, a nasogastric tube can be used to give ORS solution at about 20ml/kg/hour. This rate of NG tube infusion should not be exceeded so as to avoid abdominal distension and repeated vomiting.

W• ORS should not be given to patients who have paralytic ileus

Common electrolyte abnormalities

How are they treated?

Hypokalaemia: Serum K+ <3.5mmol/L

• Hyponatraemia: Serum Na+ <135mmol/L

• Hypernatraemia: Serum Na+ >150mmol/L

• Metabolic acidosis: Serum bicarbonate <20mmol/L

With ORS!

Old ORS consists of?

New ORS consists of?

90mmol/L of sodium

111mmol/L of glucose

80mmol/L of chloride,

20mmol/L of potassium

10mmol/L of citrate (equivalent to about 30mmol/L of bicarbonate) , giving a total osmolarity of 311 mmol/L.

75mmol/L of sodium,

75mmol/L of glucose,

and 65mmol/L of chloride

20mmol/L of potassium,

10mmol/L of citrate (equivalent to about 30mmol/L of bicarbonate)

, giving a total osmolarity of 245 mmol/L.

Reduced stool output and vomiting during treatment

How to prepare SSS

SSS is prepared by adding 6 level teaspoons of sugar and half level teaspoon of salt to one litre of water.

Other treatments of diarrhea

Zinc: 10-20mg for 10-14days

Antibiotics in dysentery and cholera

Vitamin A supplements in severely malnourished children

Antibiotics

Cholera: erythromycin, azithromycin

Shigella: ceftriaxone

Amoebic dysentery: metronidazole

Giardiasis: metronidazole

Methods of transmitting malaria

Mosquitoes ingest? Inject?

Bite of a female anopheles mosquito

Blood transfusion

Congenital malaria

Gametocytes

Sporozoites

Diagnosis of severe malaria

Asexual forms of p. Falciparum on a blood film: trophozoites and schizonts

With any of the clinical or lab findings

cns: unarousable coma, multiple convulsions, prostration

Hematology: severe anaemia: haemoglobin concentration <5g/dL or a haematocrit of <15%

– haemoglobinuria: cola/dark coloured urine

circulatory collapse or shock

– jaundice

– abnormal spontaneous bleeding

Renal

– oliguria/ renal impairment

Metabolic

– hypoglycaemia: blood glucose <2.2mmol/L or <40mg/dl

Respi

– respiratory distress/ metabolic acidosis

– pulmonary oedema

Diagnosis of malaria

PBF, stains, what they stain for?

Others?

PBF🥇: thick: presence of parasites, giemsa stain

Thin: species of parasites, leishman stain

RDT: detect specific antigens produced by malaria parasites

PCR:

Recommended ACTs

Artemether + Lumefantrine (aka Coartem, Lonart, combisunate etc).

Artesunate + Amodiaquine (aka Camosunate).

Dihydroartemisinin-piperaquine (aka P- Alaxin).

Artesunate-Pyronaridine

Artesunate-Mefloquine • Artemisinin-Piperaquine

What is the dose of AL

Given twice daily (bd) for 3 days. Each tablet contains 20mg Arthemeter and 120mg Lumefantrine.

●Weight 5-14kg: 1 tablet bd

●Weight 15-24kg: 2 tablets bd

●25-34kg: 3 tablets bd

●≥35kg: 4 tablets bd

2nd dose, 8hrs after first dose on day 1. Subsequent doses 12hrs apart

Does of AA

4.5kg- <9kg (or 2-11 months): 25mg/75mg satchets

● >9kg- <18kg (or 1-6 years): 50mg/150mg satchets

● 18kg- <36kg (or 7-13 years): 100mg/300mg tablets; 1 tablet daily.

● ≥36kg (or ≥14 years): 100mg/300mg tablets; 2

Indications for admission of uncomplicated malaria

Recurrent vomiting

To pacify parental anxiety

Principles of treatment of severe malaria

Specific antimalarial treatment:

Treatment of specific complications.

Supportive treatment.

What is the dose of IV artesunate

• For children < 20 kg: 3.0 mg/kg per dose.

• For children > 20 kg and adults: 2.4 mg/kg per dose.

• Give at 0 hr, 12 hr and 24 hr, then once daily thereafter. i.e.

– Dose 1: on admission (0 hr)

– Dose 2: 12 hours later.

– Dose 3: 12 hours after second dose.

– If still very ill after 24 hours, give same dose daily until patient can tolerate oral

After which a full 3day course of ACT should be given as follow on treatment

Alternatives to IV artesunate

Intramuscular Artesunate injection.

– Intramuscular Arthemether injection: 3.2mg/kg daily for 3 days.

– Intravenous Quinine: given as infusion. Loading dose of 20mg/kg Quinine

IM quinine

Complications of quinine use

Treatment of complications and supportive treatment

To diagnose cerebral malaria

Coma: GCS<11, BCS:<3

Confirmation of asexual forms of P. falciparum on a peripheral blood smear.

• Exclusion of other causes of encephalopathy/coma

Complications of cerebral malaria

– Cortical blindness⭐️

– Motor spasticity: hemiplegia, quadriparesis

– Ataxia and dystonia

– Aphasia⭐️

– Behavioural disorders⭐️

– Impairment in attention and learning, including ADHD.⭐️

– Mental subnormality

– Seizure disorder.⭐️

Poor prognostic factors

Age <2yrs

– Repeated seizures: Seizures that are difficult to control.

– Deep and prolonged coma.

– Papilloedema/Raised intracranial pressure.

– Hypoglycaemia.

– Metabolic acidosis,