Updated on April 9, 2017
Linda R, a mom in Fort Myers, called LiceDoctors last week and asked us to come and check her family. The school nurse had found nits in her daughter's hair and had sent the daughter home from school. We made a house call to her home and did a thorough check on the hair. We found no signs of lice or nits; what we found were some dandruff and several hair casts. Many people, including nurses, mistaken hair casts for nits. Following is a detailed explanation of the differences among dandruff, hair casts, DEC plugs, and nits so that you will better be able to identify what is in your child's hair.
Nits appear brown when against a light background Nits: Nits are lice eggs; each nit has a translucent shell that encases a little brown baby louse called a nymph. When placed against a white background nits will look brown not white. The shell of the nit is very hard and is impenetrable, meaning no chemicals are able to pierce through the shell in order to kill the bug inside. Nits are about the size of a sesame seed, although when they are first laid they are microscopic. They get bigger over 10 days and then they hatch. Each nit is round on one side and pointy on the other with a tail-like antenna coming out of the pointy end. Nits are glued to the hair shaft on one side and do not flake off. Nits need the temperature of the human head to survive, therefore viable nits are close to the scalp. Nits that are found farther away from the scalp are empty casings that remain glued to the hair even though the egg has hatched. Nits camouflage in the hair and can be difficult to find. A trained lice technician is best able to locate the nits in the hair Dandruff: Dandruff is a harmless type of skin eczema, also called Seborrheic Dermatitis. It is the result of overproduction by the oil glands on the scalp. Dandruff is white and flat and flakes off the hair. On some heads, it is limited to small areas while other heads are covered with it.
Hair casts are white and elongated Fort Myers-Naples Hair casts: Pseudonits, also called hair casts, are white, narrow and cylinder-shaped. They can be sticky and since people assume that nits are white, hair casts are often mistaken for nits. Hair casts are easier to remove and are whiter than nits and they wrap around the whole hair shaft instead of just sticking to one side. They are fairly common,although many people are unaware that they have them. People may not notice the hair casts until they are looking for head lice and nits and then they will see the hair casts and think that they have found nits. Hair casts are 2-7 mm in length. If someone has hair casts, there are usually several on the head. They may accompany psoriasis or seborrhea. Hair casts are basically debris that is found in the hair. DEC plugs: Desquamated epithelial cells or DEC plugs may occur when oil glands in the scalp become over active to make up for the drying effects of chemical treatments. They are very white, irregularly shaped pieces of fat cells that stick to the hair shaft. Like hair casts, DEC plugs are often mistaken for nits. Linda in Fort Myers was relieved to learn that her child did not have nits, although she was annoyed that her daughter has been sent home from school by mistake. If your school nurse sees nits in the hair, you can ask her to put the nits against a white background. If it is not a nit, it will blend in with the white background. Nits will show up prominently as a brown with a pointy front. Call LiceDoctors today in the Fort Myers and Naples area at 239-284-1308 and we will diagnose and treat head lice and nits or let you know if you are nit-free.