- Congenital onset (HP:0003577): A phenotypic abnormality that is present at birth. Evidence: PCS. Frequency: 1/1. (PMID:14970743)
- Long philtrum (HP:0000343): Distance between nasal base and midline upper lip vermilion border more than 2 SD above the mean. Alternatively, an apparently increased distance between nasal base and midline upper lip vermilion border. Evidence: PCS. Frequency: 1/3. (PMID:14970743;PMID:15534187;PMID:1577472)
- Delayed CNS myelination (HP:0002188): Delayed myelination in the central nervous system. Evidence: PCS. Frequency: 1/1. (PMID:15534187)
- Protruding tongue (HP:0010808): Tongue extending beyond the alveolar ridges or teeth at rest. Evidence: PCS. Frequency: 1/3. (PMID:14970743;PMID:15534187;PMID:1577472)
- Hepatomegaly (HP:0002240): Abnormally increased size of the liver. Evidence: PCS. Frequency: 2/3. (PMID:14970743;PMID:15534187;PMID:1577472)
- Ataxia (HP:0001251): Ataxia refers to impaired coordination of voluntary muscle movement. Cerebellar ataxia refers to ataxia due to dysfunction of the cerebellum. This causes a variety of elementary neurological deficits including asynergy (lack of coordination between muscles, limbs and joints), dysmetria (lack of ability to judge distances that can lead to under- or overshoot in grasping movements), and dysdiadochokinesia (inability to perform rapid movements requiring antagonizing muscle groups to be switched on and off repeatedly). Evidence: PCS. Frequency: 1/2. (PMID:14970743;PMID:1577472)
- Elevated urinary coproporphyrin level (HP:6000536): The amount of a coproporphyrin in the urine, normalized for urine concentration, is above the upper limit of normal. Evidence: PCS. Frequency: 2/2. (PMID:14970743;PMID:15534187)
- Coarse facial features (HP:0000280): Absence of fine and sharp appearance of brows, nose, lips, mouth, and chin, usually because of rounded and heavy features or thickened skin with or without thickening of subcutaneous and bony tissues. Evidence: PCS. Frequency: 1/3. (PMID:14970743;PMID:15534187;PMID:1577472)
- Intention tremor (HP:0002080): A type of kinetic tremor that occurs during target directed movement is called intention tremor. That is, an oscillatory cerebellar ataxia that tends to be absent when the limbs are inactive and during the first part of voluntary movement but worsening as the movement continues and greater precision is required (e.g., in touching a target such as the patient's nose or a physician's finger). Evidence: PCS. Frequency: 1/2. (PMID:14970743;PMID:1577472)
- Cataract (HP:0000518): A cataract is an opacity or clouding that develops in the crystalline lens of the eye or in its capsule. Evidence: PCS. Frequency: 2/3. (PMID:14970743;PMID:15534187;PMID:1577472)
- Sensorimotor neuropathy (HP:0007141). Evidence: PCS. Frequency: 1/1. (PMID:15534187)
- Anemia (HP:0001903): A reduction in erythrocytes volume or hemoglobin concentration. Evidence: PCS. Frequency: 1/3. (PMID:14970743;PMID:15534187;PMID:1577472)
- Childhood onset (HP:0011463): Onset of disease at the age of between 1 and 5 years. Evidence: PCS. Frequency: 1/1. (PMID:1577472)
- Increased urine urobilinogen (HP:0031890): An elevated concentration of urobilinogen in the urine. Evidence: PCS. Frequency: 3/3. (PMID:14970743;PMID:15534187;PMID:1577472)
- Postnatal growth retardation (HP:0008897): Slow or limited growth after birth. Evidence: PCS. Frequency: 1/2. (PMID:14970743;PMID:1577472)
- Splenomegaly (HP:0001744): Abnormal increased size of the spleen. Evidence: PCS. Frequency: 2/3. (PMID:14970743;PMID:15534187;PMID:1577472)
- Red urine (HP:0040318): An abnormal red color of the urine. Evidence: PCS. Frequency: 1/3. (PMID:14970743;PMID:15534187;PMID:1577472)
- Partial absence of cerebellar vermis (HP:0002951): Congenital absence of a part of the vermis of cerebellum. Evidence: PCS. Frequency: 1/2. (PMID:14970743;PMID:1577472)
- Neonatal onset (HP:0003623): Onset of signs or symptoms of disease within the first 28 days of life. Evidence: PCS. Frequency: 1/1. (PMID:15534187)
- Hyporeflexia (HP:0001265): Reduction of neurologic reflexes such as the knee-jerk reaction. Evidence: PCS. Frequency: 1/3. (PMID:14970743;PMID:15534187;PMID:1577472)
- Axial hypotonia (HP:0008936): Muscular hypotonia (abnormally low muscle tone) affecting the musculature of the trunk. Evidence: PCS. Frequency: 1/1. (PMID:15534187)
- Babinski sign (HP:0003487): Upturning of the big toe (and sometimes fanning of the other toes) in response to stimulation of the sole of the foot. If the Babinski sign is present it can indicate damage to the corticospinal tract. Evidence: PCS. Frequency: 1/1. (PMID:15534187)
- Febrile seizure (within the age range of 3 months to 6 years) (HP:0002373): A febrile seizure is any type of seizure (most often a generalized tonic-clonic seizure) occurring with fever (at least 38 degrees Celsius) but in the absence of central nervous system infection, severe metabolic disturbance or other alternative precipitant in children between the ages of 3 months and 6 years. Evidence: PCS. Frequency: 1/2. (PMID:14970743;PMID:1577472)
- 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: PCS. Frequency: 2/3. (PMID:14970743;PMID:15534187;PMID:1577472)
- Orange urine (HP:0032002): An abnormal orange color of urine. Evidence: PCS. Frequency: 1/3. (PMID:14970743;PMID:15534187;PMID:1577472)
- Optic nerve hypoplasia (HP:0000609): Underdevelopment of the optic nerve. Evidence: PCS. Frequency: 1/1. (PMID:1577472)
- Reduced erythrocyte porphobilinogen deaminase activity (HP:4000199): Activity or concentration of in the level of porphobilinogen deaminase (EC 4.3.1.8) in erythrocytes below the lower limit of normal. Evidence: PCS. Frequency: 3/3. (PMID:14970743;PMID:15534187;PMID:1577472)
- Kyphosis (HP:0002808): Exaggerated anterior convexity of the thoracic vertebral column. Evidence: PCS. Frequency: 1/3. (PMID:14970743;PMID:15534187;PMID:1577472)
- Hyperbilirubinemia (HP:0002904): An increased amount of bilirubin in the blood. Evidence: PCS. Frequency: 1/3. (PMID:14970743;PMID:15534187;PMID:1577472)
- Yellow-brown discoloration of the teeth (HP:0006286). Evidence: PCS. Frequency: 1/2. (PMID:14970743;PMID:1577472)
- Ptosis (HP:0000508): The upper eyelid margin is positioned 3 mm or more lower than usual and covers the superior portion of the iris (objective); or, the upper lid margin obscures at least part of the pupil (subjective). Evidence: PCS. Frequency: 1/1. (PMID:15534187)
- Autosomal recessive inheritance (HP:0000007): A mode of inheritance that is observed for traits related to a gene encoded on one of the autosomes (i.e., the human chromosomes 1-22) in which a trait manifests in individuals with two pathogenic alleles, either homozygotes (two copies of the same mutant allele) or compound heterozygotes (whereby each copy of a gene has a distinct mutant allele). Evidence: PCS. (PMID:1577472)
These phenotypes are associated with the disease encephalopathy, porphyria-related (OMIM:620704).