Ascites

Question 1

Define ascites

Answer 1

Pathological collection of fluid in the peritoneal cavity

Question 2

Aetiology of ascites

Answer 2

Non-peritoneal
Portal hypertension:
- Cirrhosis
- Alcoholic liver disease
- Fulminant hepatitis e.g. paracetamol overdose
- Subacute hepatitis
- Liver metastasis
- Cardiac: Congestive heart failure | Constrictive pericarditis
- Budd-Chiari syndrome
Hypo-albuminaemia:
- Nephrotic syndrome
- Protein-losing enteropathy
Miscellaneous: myxoedema, ovarian tumours, pancreatic ascites, surgical trauma

peritoneal
Malignant:
- Peritoneal mesothelioma
- Peritoneal carcinomatosis
- Ovarian cancer
Infectious peritonitis:
- TB
- Chlamydia
- Candida
- Histoplasma
- Cryptococcus
SLE

Question 3

Clinical features of ascites

Answer 3

Abdominal distension
Abdominal discomfort/pain
Dyspnoea
Reduced mobility
Anorexia and early satiety
Shifting dullness

Question 4

investigations for ascites

Answer 4

LFTs
U&Es
VBG
FBC: thrombocytopenia suggests portal HTN
Viral serology
Serum albumin

Ascitic tap/paracentesis: cell count and differentials | albumin and total protein concentration | Serum ascites albumin gradient (SAAG) | polymorphonuclear leukocyte (PMN) | LDH
US abdomen: ?cirrhosis or malignancy
CT abdomen: ?splenomegaly (PHTN)

Question 5

How is ascites graded

Answer 5

Grade 1: mild ascites detectable only by ultrasound
Grade 2: moderate ascites with moderate symmetrical distention of abdomen
Grade 3: large or gross ascites with marked abdominal distention

Question 6

How is SAAG interpreted

Answer 6

High SAAG (>1.1g/dL) = portal HTN cause
Portal hypertension:
- Cirrhosis
- Alcoholic liver disease
- Fulminant hepatitis e.g. paracetamol overdose
- Subacute hepatitis
- Liver metastasis
- Cardiac: Congestive heart failure | Constrictive pericarditis
- Budd-Chiari syndrome

Low SAAG:
Hypo-albuminaemia:
- Nephrotic syndrome
- Protein-losing enteropathy
Miscellaneous: myxoedema, ovarian tumours, pancreatic ascites, surgical trauma
Malignant:
- Peritoneal mesothelioma
- Peritoneal carcinomatosis
- Ovarian cancer
Infectious peritonitis:
- TB
- Chlamydia
- Candida
- Histoplasma
- Cryptococcus
SLE

Question 7

How is ascitic PMN interpreted

Answer 7

> 250/mm³ = Spontaneous bacterial peritonitis → urgent abx
250/mm³ with raised LDH/positive gram stain/positive culture = perforative peritonitis → surgical emergency

Question 8

Management for ascites

Answer 8

1. Address underlying cause
2. Salt-restricted diet
3. Fluid restriction
4. Spironolactone ± furosemide if insufficient
5. Prophylactic antibiotics e.g. PO ciprofloxacin or norfloxacin (ascitic protein <15g/L)

Conduct regular therapeutic paracentesis for patients with ascites refractory to medical management, whereby the fluid is drained from the abdomen over a few hours.

Refractory → large volume paracentesis, albumin replacement, TIPS

Question 9

Complications of treatment

Answer 9

Paracentesis
Paracentesis induced circulatory dysfunction → Recurrence of ascites | Hepatorenal syndrome | Dilutional hyponatraemia
Haematoma (1%)
Haemoperitoneum
Severe haemorrhage
Infection

(Contraindicated in DIC)

Question 10

Complications of ascites

Answer 10

Spontaneous bacterial peritonitis (an infection of previously sterile ascitic fluid without apparent intra-abdominal source of infection)
Encephalopathy
Hepatorenal syndrome