Lowe disease

Lowe syndrome is an X-linked recessive disease characterized by profound mental retardation, cataracts, and renal abnormalities.

Clinical Findings

Ocular abnormalities

The cataract is the first obvious symptom in patients with Lowe syndrome. It is present at birth already. Later on patient can develop glaucoma and nystagmus.

Neurological development

Although 25% of patient may have low normal intelligence, most of them show clear intellectual impairment. Also observed are areflexia and developmental delay. Some infants develop seizures.

Kindey function

Kidney dysfunktion is not as obvious in the first place. it is normal at birth. By the first year of life, however, patients develop proximal dysfunction which includes proteinuria, aminoaciduria (characteristically sparing branched-chain amino acids), variable glucosuria, and phosphaturia. Some patients develop hypophosphatemic rickets and neophrcalcinosis. Proteinuria is to blame for progressive renal failure which in the forties leads to end stage renal failure.

Diagnosis

The diagnosis is made by the typical clinical findings. There is no specific laboratory finding in patients with Lowe syndrome, so the clinical diagnosis can be confirmed by molecular genetic diagnostics only. The latter, by providing the molecular cause, offers the possibility of prenatal diagnosis.

Laboratory tests

Along with urinary abnormalities that include proteinuria, phosphaturia, glycosuria, and amino aciduria, elevated serum creatine kinase, lactate dehydrogenase, and total serum protein are observed.

Management

Treatment is symptomatic and supportive. It includes electrolyte, bicarbonate, and vitamin D supplementation. Infants get operated on cataract. Some receive antiepileptics. At some stage renal failure requires a replacement therapy.

Systematic

Metabolic disturbances of proximal tubular function
	Cystinosis
	Dent disease
	Fanconi renotubular syndrome
	Fanconi-Bickel syndrome
	Fructose intolerance
	Galactosemia
	Glycogen storage disease 1
	Hepatorenal tyrosinemia
	Lowe disease
		OCRL
	MELAS syndrome
	Wilson disease