Failure to thrive (FTT) refers to a child whose physical growth is substantially below the norm.

Abnormally increased size of the liver.

Impaired ability to eat related to problems gathering food and getting ready to suck, chew, or swallow it.

A reduction in erythrocytes volume or hemoglobin concentration.

A reduction in the number of circulating thrombocytes.

Abnormally increased formation of dense trabecular bone tissue. Despite the increased density of bone tissue, osteopetrotic bones tend to be more fracture-prone than normal.

Bilateral bulging of the lateral frontal bone prominences with relative sparing of the midline.

Facial nerve palsy is a dysfunction of cranial nerve VII (the facial nerve) that results in inability to control facial muscles on the affected side with weakness of the muscles of facial expression and eye closure. This can either be present in unilateral or bilateral form.

Occipitofrontal (head) circumference greater than 97th centile compared to appropriate, age matched, sex-matched normal standards. Alternatively, a apparently increased size of the cranium.

Abnormal increased size of the spleen.

Atrophy of the optic nerve. Optic atrophy results from the death of the retinal ganglion cell axons that comprise the optic nerve and manifesting as a pale optic nerve on fundoscopy.

A developmental anomaly characterized by abnormal smallness of one eye.

Loss of visual acuity (implying that vision was better at a certain time point in life). Otherwise the term reduced visual acuity should be used (or a subclass of that).