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Hydrops-lactic acidosis-sideroblastic anemia-multisystemic failure syndrome(HLASA)

MedGen UID:
934728
Concept ID:
C4310761
Disease or Syndrome
Synonym: Hydrops, lactic acidosis, and sideroblastic anemia
SNOMED CT: Hydrops, lactic acidosis, sideroblastic anemia, multisystemic failure syndrome (1237349008)
 
Gene (location): LARS2 (3p21.31)
 
Monarch Initiative: MONDO:0014869
OMIM®: 617021
Orphanet: ORPHA528091

Definition

Hydrops, lactic acidosis, and sideroblastic anemia (HLASA) is an autosomal recessive multisystem disorder characterized by the onset of hydrops in utero. The severity of the hydrops and the disorder in general is highly variable. At birth, affected infants usually show poor growth, lactic acidosis, pulmonary hypertension with hypoxic respiratory insufficiency, and sideroblastic anemia. More variable features may include hepatosplenomegaly or cholestasis, hypoglycemia, pancreatic insufficiency, and micropenis or hypospadias. Death in infancy may occur. Those who survive tend to have resolution of lactic acidosis and anemia, but may show developmental delay and sensorineural deafness (summary by Riley et al., 2020). [from OMIM]

Clinical features

From HPO
Hematuria
MedGen UID:
5488
Concept ID:
C0018965
Disease or Syndrome
The presence of blood in the urine. Hematuria may be gross hematuria (visible to the naked eye) or microscopic hematuria (detected by dipstick or microscopic examination of the urine).
Patent ductus arteriosus
MedGen UID:
4415
Concept ID:
C0013274
Congenital Abnormality
In utero, the ductus arteriosus (DA) serves to divert ventricular output away from the lungs and toward the placenta by connecting the main pulmonary artery to the descending aorta. A patent ductus arteriosus (PDA) in the first 3 days of life is a physiologic shunt in healthy term and preterm newborn infants, and normally is substantially closed within about 24 hours after bith and completely closed after about three weeks. Failure of physiologcal closure is referred to a persistent or patent ductus arteriosus (PDA). Depending on the degree of left-to-right shunting, PDA can have clinical consequences.
Ventricular septal defect
MedGen UID:
42366
Concept ID:
C0018818
Congenital Abnormality
A hole between the two bottom chambers (ventricles) of the heart. The defect is centered around the most superior aspect of the ventricular septum.
Hypertensive disorder
MedGen UID:
6969
Concept ID:
C0020538
Disease or Syndrome
The presence of chronic increased pressure in the systemic arterial system.
Second degree atrioventricular block
MedGen UID:
75546
Concept ID:
C0264906
Disease or Syndrome
An intermittent atrioventricular block with failure of some atrial impulses to conduct to the ventricles, i.e., some but not all atrial impulses are conducted through the atrioventricular node and trigger ventricular contraction.
Overriding aorta
MedGen UID:
120559
Concept ID:
C0265886
Congenital Abnormality
An overriding aorta is a congenital heart defect where the aorta is positioned directly over a ventricular septal defect, instead of over the left ventricle. The result is that the aorta receives some blood from the right ventricle, which reduces the amount of oxygen in the blood. It is one of the four conditions of the Tetralogy of Fallot. The aortic root can be displaced toward the front (anteriorly) or directly above the septal defect, but it is always abnormally located to the right of the root of the pulmonary artery. The degree of override is quite variable, with 5-95% of the valve being connected to the right ventricle.
Pulmonary arterial hypertension
MedGen UID:
425404
Concept ID:
C2973725
Disease or Syndrome
Pulmonary hypertension is defined mean pulmonary artery pressure of 25mmHg or more and pulmonary capillary wedge pressure of 15mmHg or less when measured by right heart catheterisation at rest and in a supine position.
Fetal growth restriction
MedGen UID:
4693
Concept ID:
C0015934
Pathologic Function
An abnormal restriction of fetal growth with fetal weight below the tenth percentile for gestational age.
Small for gestational age
MedGen UID:
65920
Concept ID:
C0235991
Finding
Smaller than normal size according to sex and gestational age related norms, defined as a weight below the 10th percentile for the gestational age.
Ascites
MedGen UID:
416
Concept ID:
C0003962
Disease or Syndrome
Accumulation of fluid in the peritoneal cavity.
Decreased liver function
MedGen UID:
65430
Concept ID:
C0232744
Finding
Reduced ability of the liver to perform its functions.
Seizure
MedGen UID:
20693
Concept ID:
C0036572
Sign or Symptom
A seizure is an intermittent abnormality of nervous system physiology characterized by a transient occurrence of signs and/or symptoms due to abnormal excessive or synchronous neuronal activity in the brain.
EEG abnormality
MedGen UID:
56235
Concept ID:
C0151611
Finding
Abnormality observed by electroencephalogram (EEG), which is used to record of the brain's spontaneous electrical activity from multiple electrodes placed on the scalp.
Anemia
MedGen UID:
1526
Concept ID:
C0002871
Disease or Syndrome
A reduction in erythrocytes volume or hemoglobin concentration.
Sideroblastic anemia
MedGen UID:
8067
Concept ID:
C0002896
Disease or Syndrome
Sideroblastic anemia results from a defect in the incorporation of iron into the heme molecule. A sideroblast is an erythroblast that has stainable deposits of iron in cytoplasm (this can be demonstrated by Prussian blue staining).
Erythroid hyperplasia
MedGen UID:
4536
Concept ID:
C0014800
Disease or Syndrome
Increased count of erythroid precursor cells, that is, erythroid lineage cells in the bone marrow.
Thrombocytopenia
MedGen UID:
52737
Concept ID:
C0040034
Disease or Syndrome
A reduction in the number of circulating thrombocytes.
Increased mean corpuscular volume
MedGen UID:
81303
Concept ID:
C0302845
Finding
Larger than normal size of erythrocytes.
Extramedullary hematopoiesis
MedGen UID:
392862
Concept ID:
C2613439
Disease or Syndrome
The process of hematopoiesis occurring outside of the bone marrow (in the liver, thymus, and spleen) in the postnatal organisms.
Respiratory insufficiency
MedGen UID:
11197
Concept ID:
C0035229
Pathologic Function
Impairment of gas exchange within the lungs secondary to a disease process, neoplasm, or trauma, possibly resulting in hypoxia, hypercarbia, or both, but not requiring intubation or mechanical ventilation. Patients are normally managed with pharmaceutical therapy, supplemental oxygen, or both.
Lactic acidosis
MedGen UID:
1717
Concept ID:
C0001125
Disease or Syndrome
An abnormal buildup of lactic acid in the body, leading to acidification of the blood and other bodily fluids.
Metabolic acidosis
MedGen UID:
65117
Concept ID:
C0220981
Pathologic Function
Metabolic acidosis (MA) is characterized by a fall in blood pH due to a reduction of serum bicarbonate concentration. This can occur as a result of either the accumulation of acids (high anion gap MA) or the loss of bicarbonate from the gastrointestinal tract or the kidney (hyperchloremic MA). By definition, MA is not due to a respirary cause.
Hypoalbuminemia
MedGen UID:
68694
Concept ID:
C0239981
Finding
Reduction in the concentration of albumin in the blood.
Increased circulating lactate concentration
MedGen UID:
332209
Concept ID:
C1836440
Finding
Abnormally increased level of blood lactate (2-hydroxypropanoic acid). Lactate is produced from pyruvate by lactate dehydrogenase during normal metabolism. The terms lactate and lactic acid are often used interchangeably but lactate (the component measured in blood) is strictly a weak base whereas lactic acid is the corresponding acid. Lactic acidosis is often used clinically to describe elevated lactate but should be reserved for cases where there is a corresponding acidosis (pH below 7.35).
Oligohydramnios
MedGen UID:
86974
Concept ID:
C0079924
Pathologic Function
Diminished amniotic fluid volume in pregnancy.
Non-immune hydrops fetalis
MedGen UID:
105327
Concept ID:
C0455988
Disease or Syndrome
Hydrops fetalis is a descriptive term for generalized edema of the fetus, with fluid accumulation in extravascular components and body cavities. It is not a diagnosis in itself, but a symptom and end-stage result of a wide variety of disorders. In the case of immune hydrops fetalis, a frequent cause is maternofetal incompatibility as in that related to a number of genetic anemias and metabolic disorders expressed in the fetus; in other instances, it remains idiopathic and likely multifactorial (summary by Bellini et al., 2009). Nonimmune hydrops fetalis accounts for 76 to 87% of all described cases of hydrops fetalis (Bellini et al., 2009). Genetic Heterogeneity of Hydrops Fetalis In southeast Asia, alpha-thalassemia (604131) is the most common cause of hydrops fetalis, accounting for 60 to 90% of cases. Almost all of these cases result from homozygous deletion of the HBA1 (141800) and HBA2 (141850) genes. A few cases have been reported that had 1 apparently normal alpha-globin gene, termed the hemoglobin H (613978) hydrops fetalis syndrome (summary by Chui and Waye, 1998). Other genetic disorders predisposing to NIHF include other congenital anemias, such as erythropoietic porphyria (e.g., 606938.0013), and many metabolic disorders, such as one form of Gaucher disease (e.g., 606463.0009), infantile sialic acid storage disease (269920), mucopolysaccharidosis type VII (253220), glycogen storage disease IV (232500), congenital disorder of glycosylation type Ia (212065), and disorders of lymphatic malformation (see, e.g., LMPHM1, 153100).
Fetal pericardial effusion
MedGen UID:
759278
Concept ID:
C3532165
Pathologic Function
An abnormal accumulation of fluid in which the heart is partially or completely surrounded by fluid that is seen in all views and the thickness of the fluid as observed by prenatal ultrasound is above age-dependent norms.

Term Hierarchy

CClinical test,  RResearch test,  OOMIM,  GGeneReviews,  VClinVar  
  • CROGVHydrops-lactic acidosis-sideroblastic anemia-multisystemic failure syndrome

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