Nail-patella syndrome: Year of the Zebra

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Nail-patella syndrome, or NPS for short, also known as hereditary onycho-osteodysplasia or Fong disease, is a rare genetic disorder caused by a mutation in the LMX1B gene.
The mutated gene is inherited with an autosomal dominant pattern, meaning only one copy of the defective gene is necessary to have the disorder.
The LMX1B gene plays an important role in development, most notably, of a fetus’s nails, skeletal system, kidneys, and eyes, among others.
For affected individuals, the mutated gene leads to a disruption in the normal development of these systems. Now, nail-patella syndrome may present with a variety of symptoms most often affecting the nails, skeletal system, kidneys, and eyes, with most symptoms varying between affected family members.
The most consistent clinical manifestation involves nail changes, like absent, underdeveloped, split, ridged, or pitted nails, which most commonly affect the thumbnails, with the changes decreasing in frequency with each finger.
Next, the kneecaps, or patellae, arms, and pelvis of the skeletal system may be affected. The kneecaps may be small, with an irregular shape, or even absent.
These deformities make the kneecaps easily dislocate, unstable, and oftentimes painful. When the arms are affected, individuals may have extra webbing around their elbows; experience difficulty extending their arms; or difficulty supinating their arms, which involves rotating the forearm so the palm is facing upwards.
Affected individuals typically also have iliac horns, or horn-like outgrowths on the pelvis, which are usually non-painful and found during imaging.
Lastly, the kidneys and eyes can also be affected. If the kidneys are affected, blood and protein may be found in the urine, and kidney failure may occur in some individuals.
If the eyes are affected, individuals can have glaucoma, which is increased pressure in their eyes, and can present earlier in life compared to unaffected individuals.
Alright, so the diagnosis of nail-patella syndrome is based on the individual's history and physical examination, with genetic testing to confirm the diagnosis.
Additional imaging, like x-rays or MRI, can help identify skeletal abnormalities. Other laboratory tests or imaging can help evaluate involvement of other body systems, like the kidneys or eyes.
There is no cure for nail-patella syndrome, so treatment focuses on managing each individual’s symptoms. Skeletal deformities may be treated with analgesics, physiotherapy, or surgery, in some cases.
If the kidneys are affected, management may include medications like angiotensin-converting enzyme inhibitors, dialysis, or even kidney transplantation.
Lastly, glaucoma treatment may involve the use of eye drops to reduce the pressure inside the eye, or surgery. Alright, as a quick recap, nail-patella syndrome is a rare multisystem disorder due to a mutation in the LMX1B gene and characterized by nail changes, skeletal deformities, and renal and eye changes.
Diagnosis is based on history, physical examination, and genetic testing. Treatment focuses on managing each individual’s symptoms.
as a quick recap nail patella syndrome is a rare multi system disorder due to a mutation in the L M X one B gene and is characterized by nail changes skeletal deformities and renal and I changes Diagnosis is based on history physical examination and genetic testing treatment focuses on managing each individual