Placental Aromatase Deficiency
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1] Associate Editor(s)-in-Chief:
Overview
Aromatase deficiency is an autosomal recessive disorder in which there is a decrease or absence in the level of aromatase in the body which leads to impairment in the conversion of androgens to estrogen. This is due to a genetic mutation in the CYP19A1, a subtype of [P450]. Patient affected by this disease typically presents with maternal virilization, amenorrhea in puberty in females. Males are rarely affected.
Historical Perspective
- The evidence of the disease goes back to year 1991, when the first case of aromatase deficiency occurred in 24year old primigravida and the female fetus showed pseudohermaphroditism.[1]
- Most of the cases were that of women during the third trimester of pregnancy presenting with maternal virilization resulting in hirsutism and acne.
Classification
- There is no established system for the classification of Placental Aromatase Deficency.
Pathophysiology
- CYP19A1 gene is responsible for the production of enzyme aromatase, which converts androgens to different forms of estrogen
- Mutation is inherited in an autosomal recessive mode.
- Estrogen is involved in sexual development in females prior to birth and the levels peak during pregnancy. Mutation in CYP19A1 gene leads to deficiency or absence of activity of aromatase .
- As a result, there is decrease in production of estrogen due to lack of conversion of androgens to estrogen and increase in testosterone and androstenedione levels.
- In pregnant women , excess androgens cross the placenta and enter into the maternal circulation leading to virilization. Female fetuses who are affected have ambiguous genitalia while males develop osteoporosis.
Causes
- CYP19A1 gene mutation primarily causes Placental Aromatase Deficiency and the placenta is not capable of converting androgenic precursors of estrogen to estradiol. Mutations on exons 3,5 and 9 have been reported.
- Studies suggest that it is more prevalent in consanguineous marriages and both are heterozygous carriers of the mutation.[2]
Differentiating Any Disease from other Diseases
- Congenital adrenal hyperplasia can be considered as a differential in female patients.
While, in male patients;
- 5 alpha reductase deficiency :The levels of testosterone and estrogen are normal.
- Estrogen resistance syndrome
- 46,XY disorder of sex development due to isolated 17, 20 lyase deficiency.
- Congenital adrenal hyperplasia due to cytochrome P450 oxidoreductase deficiency.
- Congenital hypogonadotropic hypogonadism.
- can be considered as the differential diagnosis of Placental Aromatase Deficiency.
Epidemiology and Demographics
- Placental Aromatase Deficiency is a rare autosomal recessive disorder.
- The prevalence is unknown . [3]
- There are only few cases that have been described in the literature.
Risk Factors
- The risk factors evident with placental aromatase deficiency includes placental ischemia and preeclampsia .[4]
Screening
- There is insufficient evidence to recommend routine screening for Placental aromatase deficiency.
Natural History , Complications and Prognosis
- Placental aromatase deficiency is a rare entity.
- Defective synthesis of estrogen in aromatase deficiency may result in :
- Delayed Puberty
- Insulin resistance
- Polycystic ovary syndrome
- Bone disorders like osteoporosis
- In patients with Aromatase deficiency lifetime hormone replacement therapy is mandatory. We can see osteoporosis as an outcome in male patients with late diagnosis, and these skeletal defects tend to remain even after hormonal treatment and sometimes require surgical correction. Moreover, the effects on glucose and lipid metabolism like adiposity and reproductive defects such as infertility are also not corrected by estradiol treatment.
Diagnosis
Diagnostic Study of Choice
The diagnosis of [disease name] is made when at least [number] of the following [number] diagnostic criteria are met: [criterion 1], [criterion 2], [criterion 3], and [criterion 4].
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The diagnosis of [disease name] is based on the [criteria name] criteria, which include [criterion 1], [criterion 2], and [criterion 3].
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The diagnosis of [disease name] is based on the [definition name] definition, which includes [criterion 1], [criterion 2], and [criterion 3].
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There are no established criteria for the diagnosis of [disease name].
History and Symptoms
The majority of patients with [disease name] are asymptomatic.
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The hallmark of [disease name] is [finding]. A positive history of [finding 1] and [finding 2] is suggestive of [disease name]. The most common symptoms of [disease name] include [symptom 1], [symptom 2], and [symptom 3]. Common symptoms of [disease] include [symptom 1], [symptom 2], and [symptom 3]. Less common symptoms of [disease name] include [symptom 1], [symptom 2], and [symptom 3].
Physical Examination
Patients with [disease name] usually appear [general appearance]. Physical examination of patients with [disease name] is usually remarkable for [finding 1], [finding 2], and [finding 3].
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Common physical examination findings of [disease name] include [finding 1], [finding 2], and [finding 3].
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The presence of [finding(s)] on physical examination is diagnostic of [disease name].
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The presence of [finding(s)] on physical examination is highly suggestive of [disease name].
Laboratory Findings
An elevated/reduced concentration of serum/blood/urinary/CSF/other [lab test] is diagnostic of [disease name].
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Laboratory findings consistent with the diagnosis of [disease name] include [abnormal test 1], [abnormal test 2], and [abnormal test 3].
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[Test] is usually normal among patients with [disease name].
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Some patients with [disease name] may have elevated/reduced concentration of [test], which is usually suggestive of [progression/complication].
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There are no diagnostic laboratory findings associated with [disease name].
Electrocardiogram
There are no ECG findings associated with [disease name].
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An ECG may be helpful in the diagnosis of [disease name]. Findings on an ECG suggestive of/diagnostic of [disease name] include [finding 1], [finding 2], and [finding 3].
X-ray
There are no x-ray findings associated with [disease name].
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An x-ray may be helpful in the diagnosis of [disease name]. Findings on an x-ray suggestive of/diagnostic of [disease name] include [finding 1], [finding 2], and [finding 3].
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There are no x-ray findings associated with [disease name]. However, an x-ray may be helpful in the diagnosis of complications of [disease name], which include [complication 1], [complication 2], and [complication 3].
Echocardiography or Ultrasound
There are no echocardiography/ultrasound findings associated with [disease name].
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Echocardiography/ultrasound may be helpful in the diagnosis of [disease name]. Findings on an echocardiography/ultrasound suggestive of/diagnostic of [disease name] include [finding 1], [finding 2], and [finding 3].
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There are no echocardiography/ultrasound findings associated with [disease name]. However, an echocardiography/ultrasound may be helpful in the diagnosis of complications of [disease name], which include [complication 1], [complication 2], and [complication 3].
CT scan
- There are no CT scan findings associated with [Placental Aromatase Deficiency].
MRI
- There are no MRI findings associated with Placental Aromatase Deficiency.
Other Imaging Findings
- There are no other imaging findings associated with Placental Aromatase Deficiency.
Other Diagnostic Studies
- There are no other diagnostic studies associated with Placental Aromatase Deficiency.
Treatment
Reference
- ↑ Shozu M, Akasofu K, Harada T, Kubota Y (1991). "A new cause of female pseudohermaphroditism: placental aromatase deficiency". J Clin Endocrinol Metab. 72 (3): 560–6. doi:10.1210/jcem-72-3-560. PMID 1825497.
- ↑ Ludwikowski B, Heger S, Datz N, Richter-Unruh A, González R (2013). "Aromatase deficiency: rare cause of virilization". Eur J Pediatr Surg. 23 (5): 418–22. doi:10.1055/s-0032-1324798. PMID 23093430.
- ↑ Baykan EK, Erdoğan M, Özen S, Darcan Ş, Saygılı LF (2013). "Aromatase deficiency, a rare syndrome: case report". J Clin Res Pediatr Endocrinol. 5 (2): 129–32. doi:10.4274/Jcrpe.970. PMC 3701920. PMID 23748068.
- ↑ Perez-Sepulveda A, Monteiro LJ, Dobierzewska A, España-Perrot PP, Venegas-Araneda P, Guzmán-Rojas AM; et al. (2015). "Placental Aromatase Is Deficient in Placental Ischemia and Preeclampsia". PLoS One. 10 (10): e0139682. doi:10.1371/journal.pone.0139682. PMC 4596497. PMID 26444006.