Dr Eisman explained a range of these to Mamamia:

Clubbing of the fingernails

This can be a sign of lung cancer or liver, heart and lung disease, like the side effect of lung cancer that my Aunty experienced.

Dr Eisman explained that it is only, “very rarely that fingernails can develop clubbing” so this is a definite red flag and should be shown to a medical professional.

“Clubbing means that the fingertips enlarge and the nail curvature over the tip changes (and look like the tip of drum sticks). This is likely due to decrease oxygen flow to the fingertips and can happen in lung cancer but can happen in other conditions such as liver, heart and lung diseases and AIDS. It can also be a familial occurrence, a normal occurrence in some family members.”

Yellow nail syndrome

This can also be a cause of lung disease.

“Yellow nail syndrome is a disorder that can cause yellow nails, lymphoedema (leg swelling) and lung disease. To diagnose the disorder, two of the three features need to be present either currently or in the past: slow nail growth, over curvature of the nail and absence of the cuticle and nail plate separation. The nail plate is not always yellow but can range from pale yellow to orange.”

Onycholysis, or nail plate separation

This can be a sign of thyroid problems.

“Onycholysis refers to detachment or separation of the nail plate from the nail bed. It usually starts at the edge of the nail and progresses towards the cuticle. The detached nail appears white-yellow because of air trapped in the layer between the nail plate and the nail bed.”

“Onycholysis may be due to a skin condition, eczema or fungal nail infection, medication, sunlight, thyroid problems or manicuring.”

Dr Eisman says, “when in doubt it is best to seek medical advice.”

Dr Samantha Eisman MBChB MRCP(UK) FCDerm(SA) FACD is a Consultant Dermatologist at Sinclair Dermatology.