Jaundice is defined as yellowish discoloration of sclera, mucous membrane, nailbed of skin due to excess amount of serum bilirubin of > 2 mg/dl.
Subclinical jaundice -Serum bilirubin 1-2 mg/dl
Normal - serum bilirubin < 1 mg/dl
What is latent jaundice?
The normal serum bilirubin level is 0.3-1.0 mg/dl. Clinical jaundice is evident only when scrum bilirubin exeeds 2.5 mg/d .Jaundice is said to be latent, i.e. when it is clinically non-evident and detected only by serum analysis.This is seen when the serum bilirubin level is in between l-2.5mg/dl.
What are the sites you should examine for jaundice ?
Upper bulbar conjunctiva is examined after retract the uppereyelid and ask the patient to look downwards both eye should be examined at a time
- Undersurface of tongue.
- Soft palate.
- Palms and soles.
- General skin surface.
While examining for jaundice first elevate the upper eyelid, Then ask the patient to look down and then look at the periphery of the sclera in bright natural day light
As in the artificial light you cannot detect the light yellow discolouration of sclera always examine the patient in the natural light.You should take the patient in front of an open window for examination of jaundice.
Why the upper bulbar conjunctiva is selected for examination of jaundice?
- A white background is formed by sclera.
- Sclera of eye is rich in elastic fibers.Serum bilirubin has affinity to elastic fibers. Periphery of the sclera is thick with more elastic fiber so early staining by bilirubin will occur at the periphery. In case of marked hyperbilirubinemia, all tissues except the brain is stained by bilirubin, the brain is not stained due the blood-brain barrier block the bilirubin staining of the brain.
Hemolytic anemia —This is a lemon yellow jaundice, Urine colour is normal no yellowish discolouration of urine hence called acholuric jaundice.
Hepatocellular jaundice jaundice- Hyper bilirubinuria with other stigmas of hepatocellular damage and other features of primary liver disease may be seen.
Obstructive jaundice –is characterised by greenish dark yellow jaundice, pruritus, pale stool, palpable gallbladder.
This is seen in either intra-or extra- hepatic cholestasis.
Differential diagnosis of jaundice
Carotinemia is a condition characterized by yellowish discoloration of skin (carotenoderma) that spare the sclera and mucous membrane.
What are the diseases commonly present as latent jaundice?
- Mitral stenosis (passive venous congestion of liver).
- Myocardial infarction.
- Cirrhosis of liver.
- Pernicious anaemia.
- Acute pancreatitis.
- Pulmonary infarction (acute pulmonary thromboembolism).
- Congestive cardiac failure.
Gilbert's syndrome.
Crigler-Najjar syndrome.
Dubin-Johnson syndrome.
Rotor syndrome.