- Diffuse mesangial sclerosis (HP:0001967): Thickening and scarring (sclerosis) of the mesangium (a structure in the glomerulus). The sclerosis affects a large portion of the mesangium across multiple glomeruli. Histologic features include an increase in the mesangial matrix, thickened glomerular basement membrane, tubular casts, and interstitial inflammation. Diffuse mesangial sclerosis presents with nephrotic syndrome at birth or within the first year of life. Glomeruli are small and condensed in appearance, with early lesions showing increased loose mesangial collagen that progress to sclerosis with dense collagen without hypercellularity. Podocytes do not show hyperplasia but may be immature and cobblestone-like. Electron microscopy shows extensive foot process effacement without deposits, but increased collagen within mesangial areas. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:2670)
- Congenital nephrotic syndrome (HP:0008677): Nephrotic syndrome with onset within the first three months of life. Evidence: TAS. Frequency: Very frequent (HP:0040281). (ORPHA:2670)
- Renal insufficiency (HP:0000083): A reduction in the level of performance of the kidneys in areas of function comprising the concentration of urine, removal of wastes, the maintenance of electrolyte balance, homeostasis of blood pressure, and calcium metabolism. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:2670)
- Cataract (HP:0000518): A cataract is an opacity or clouding that develops in the crystalline lens of the eye or in its capsule. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:2670)
- Nystagmus (HP:0000639): Rhythmic, involuntary oscillations of one or both eyes related to abnormality in fixation, conjugate gaze, or vestibular mechanisms. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:2670)
- Macular hypoplasia (HP:0001104): Underdevelopment of the macula lutea. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:2670)
- Hypotonia (HP:0001252): Hypotonia is an abnormally low muscle tone (the amount of tension or resistance to movement in a muscle). Even when relaxed, muscles have a continuous and passive partial contraction which provides some resistance to passive stretching. Hypotonia thus manifests as diminished resistance to passive stretching. Hypotonia is not the same as muscle weakness, although the two conditions can co-exist. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:2670)
- Global developmental delay (HP:0001263): A delay in the achievement of motor or mental milestones in the domains of development of a child, including motor skills, speech and language, cognitive skills, and social and emotional skills. This term should only be used to describe children younger than five years of age. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:2670)
- Motor delay (HP:0001270): A type of Developmental delay characterized by a delay in acquiring motor skills. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:2670)
- Oligohydramnios (HP:0001562): Diminished amniotic fluid volume in pregnancy. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:2670)
- Feeding difficulties in infancy (HP:0008872): Impaired feeding performance of an infant as manifested by difficulties such as weak and ineffective sucking, brief bursts of sucking, and falling asleep during sucking. There may be difficulties with chewing or maintaining attention. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:2670)
- Microcoria (HP:0025492): A small pupil (typically diameter less than 2 mm) that dilates poorly or not at all in response to topically administered mydriatic drugs. Evidence: TAS. Frequency: Frequent (HP:0040282). (ORPHA:2670)
- Visual impairment (HP:0000505): Visual impairment (or vision impairment) is vision loss (of a person) to such a degree as to qualify as an additional support need through a significant limitation of visual capability resulting from either disease, trauma, or congenital or degenerative conditions that cannot be corrected by conventional means, such as refractive correction, medication, or surgery. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:2670)
- Hyporeflexia (HP:0001265): Reduction of neurologic reflexes such as the knee-jerk reaction. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:2670)
- Hypoplasia of the iris (HP:0007676): Congenital underdevelopment of the iris. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:2670)
- Remnants of the hyaloid vascular system (HP:0007968): Persistence of the hyaloid artery, which is the embryonic artery that runs from the optic disc to the posterior lens capsule may persist; the site of attachment may form an opacity. The hyaloid artery is a branch of the ophthalmic artery, and usually regresses completely before birth. This features results from a failure of regression of the hyaloid vessel, which supplies the primary vitreous during embryogenesis and normally regresses in the third trimester of pregnancy, leading to a particular form of posterior cataract. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:2670)
- Spherophakia (HP:0034375): Spherophakia is a rare congenital condition that presents with weak zonules around a more spherical crystalline lens with an increased anteroposterior thickness of the lens, and highly myopic eye. The lens zonules are developmentally hypoplastic and abnormally weak and due to non-attachment of the posterior zonules to the equatorial zone of the lens, the lens changes its normal shape to spherical. Evidence: TAS. Frequency: Occasional (HP:0040283). (ORPHA:2670)
These phenotypes are associated with the disease Pierson syndrome (ORPHA:2670).