≤11 ribs is associated with a number of congenital abnormalities and skeletal dysplasias, including:
Down syndrome (trisomy 21)
asphyxiating thoracic dysplasia (Jeune syndrome)
short rib polydactyly syndromes
chromosome 1q21.1 deletion...
18q-deletion syndrome is a rare chromosomal anomaly where there is a deletion of part of the long arm of chromosome 18. Associated symptoms and findings vary widely, as do their severity. Characteristic clinical features include short stature, intellectual disability, hypotonia, facial and dista...
1p36 deletion syndrome, or monosomy 1p36, is a chromosomal abnormality characterized most commonly by a deletion in the distal segment of the short arm of chromosome one 1.
The 1p36 deletion syndrome is present in approximately 1 in 5000 live births. It is the most common terminal...
4D syndrome is a term used to describe a manifestation of syndromic glucagonomas, a type of pancreatic endocrine tumor.
D: dermatitis 2
necrolytic migratory erythema - a widespread rash, tending to involve perioral and perigenital regions
oral rashes (angular stomatitis, cheilitis)
tend to r...
Aarskog syndrome or Aarskog–Scott syndrome (also known as the facio-digito-genital syndrome) is a rare anomaly characterized by short stature in association with a variety of structural anomalies involving mainly the face, distal extremities, and external genitalia.
Aase-Smith syndrome (or Aase syndrome) is an extremely rare congenital disorder.
congenital hypoplastic anemia - fetal anemia
cleft lip or cleft palate
hydrocephalus (due to Dandy-Walker anomaly)
Abdominal migraine (AM) is a syndrome which presents as recurrent episodes of severe abdominal pain, coupled with vasomotor symptoms, nausea and emesis. Historically it has tended to be a pediatric diagnosis, but is now increasingly seen in adults. It is one of the functional gastrointestinal di...
Acardius anephus is a morphologic subtype of an acardiac twin in the twin reversed arterial perfusion (TRAP) sequence. In this entity, no cephalic or structures are present, but the lower limbs are preserved. This is the most common subtype, seen in 60-75% of cases1.
Accessory navicular syndrome occurs when a type II accessory navicular becomes painful due to movement across the pseudo-joint between the ossicle and the navicular bone.
It can be inferred on musculoskeletal ultrasound if a patient's pain is located at a type...
Achondrogenesis refers to a group of rare and extreme skeletal dysplasias.
The estimated incidence is 1:40,000 with no recognized gender predilection.
It is classified as an osteochondrodysplasia, meaning deficiency of both bone and cartilage development.
Acrocephalosyndactyly syndromes (ACS) are a rare group of disorders collectively characterized by:
calvarial anomalies, e.g. craniosynostoses
digital anomalies, e.g. syndactyly
While there can be some overlap in features, they can be primarily classified into the following maj...
Acrodysostosis is a rare skeletal dysplasia characterized by growth retardation, nasal hypoplasia, brachydactyly, midfacial deficiency, intellectual disability and deafness.
Most cases are sporadic. Few cases with autosomal dominant transmission have been reported. It is believed to ...
Acute aortic syndrome (AAS) describes the presentation of patients with one of a number of life threatening aortic pathologies that give rise to aortic symptoms.
The spectrum of these aortic emergencies include:
aortic intramural hematoma
penetrating atherosclerotic ulcer
Acute compartment syndrome is a limb and life-threatening surgical emergency. It is a painful condition caused by increased intracompartmental pressure, compromising perfusion and resulting in muscle and nerve damage within that compartment.
Acute compartment syndrome is more comm...
Acute coronary syndrome (ACS) is a group of cardiac diagnoses along a spectrum of severity due to the interruption of coronary blood flow to the myocardium, which in decreasing severity are:
ST elevation myocardial infarction (STEMI)
non-ST elevation myocardial infarction (NSTEMI)
Acute respiratory distress syndrome (ARDS) is a form of acute lung injury (ALI) and occurs as a result of a severe pulmonary injury that causes alveolar damage heterogeneously throughout the lung. It can either result from a direct pulmonary source or as a response to systemic injury.
Acute spinal cord ischemia syndrome is uncommon, but usually presents with profound neurological signs and symptoms, and the prognosis is poor.
Acute spinal cord ischemia syndrome represents only 5-8% of acute myelopathies 4,5 and <1% of all strokes 7. The demographic of affected...
The Adams-Oliver syndrome (AOS) is a rare disorder characterized by aplasia cutis congenita (missing hair and/or skin) and variable degrees of terminal transverse limb defects.
polymicrogyria: can be associated with a variant of Adams-Oliver syndrome 3
Adductor canal syndrome (also known as adductor canal compression syndrome) is a rare, non-atherosclerotic cause of arterial occlusion and limb ischemia 1. There is compression of the superficial femoral artery (SFA) in the adductor canal.
External compression of the superficial f...
Adie syndrome, also known as Holmes-Adie syndrome, is a rare neurological disorder.
Adie syndrome is a rare condition which is most commonly seen in young females in their fourth decade of life 2,3.
Patients most commonly present with a classic triad of:
Aicardi-Goutières syndrome is a rare hereditary neurodegenerative disease which usually presents in early infancy with systemic and central nervous system inflammatory syndrome characterized by hepatosplenomegaly, vasculopathy and encephalopathy. Many of the features are similar to congenital TO...
Aicardi syndrome is a rare severe developmental disorder. It results from an X-linked genetic defect that is fatal in males and therefore only manifests in females (except for rare 47, XXY cases).
Note: Aicardi syndrome is distinct from Aicardi-Goutieres syndrome although both are named after J...
Alagille syndrome (AGS) is a congenital genetic multi-system disorder.
Infants typically present with symptoms relating to the liver where it is one of the most common causes of hereditary cholestasis.
Alagille syndrome is inherited in an autosomal fashion with...
Allgrove syndrome (also known as triple A syndrome) is an autosomal recessive condition that consists of three main findings:
All-trans retinoic acid (ATRA) syndrome, more recently known as differentiation syndrome (DS) 8, is a condition that can occur with patients with acute promyelocytic leukemia who are on therapeutic all-trans-retinoic acid (ATRA).
All-trans-retinoic acid (ATRA) is a normal constituent of plasma ...
Alpers syndrome, also known as Alpers-Huttenlocher syndrome or progressive cerebral poliodystrophy, is a rare childhood neurodegenerative POLG-related disorder. Along with Leigh syndrome, it is one of the commonest childhood mitochondrial disorders 1.
Alpers syndrome is incredibl...
Alpha-thalassemia/intellectual disability syndrome X-linked (ATRX) gene is an important genomic marker of gliomas and is either intact (ATRX wild-type) or mutated (ATRX-mutant) and is correlated with other important genomic markers including IDH, 1p19q codeletion and p53 expression 1,2.
Alport syndrome is an X-linked dominant disease characterized by progressive sensorineural hearing loss, renal disease and, at times, ocular lesions.
sensorineural hearing loss: typically high frequency 2
anterior lenticonus: most common ...
Amelia refers to a skeletal dysplasia characterized by the complete absence of upper or lower extremity or all four limbs. It may be associated with other congenital anomalies, i.e. omphalocele and diaphragmatic hernias 3.
Amelia is a very rare congenital anomaly with an incidence...
Amniotic band syndrome (ABS) comprises of a wide spectrum of abnormalities, all of which result from entrapment of various fetal body parts in a disrupted amnion. Due to the randomness of entrapment, each affected individual has the potential to form a unique deficit.
Androgen insensitivity syndrome (AIS), also known as the testicular feminisation syndrome, results from end-organ resistance to androgens, particularly testosterone. AIS may be complete or incomplete with variable imaging findings.
The incidence may vary depending on whether it i...
Anterior ankle impingement (AAI) syndrome is the result of chronic repetitive trauma with impingement of the anterior tibia against the talus.
Clinical features of anterior ankle impingement syndrome include painful and limited dorsiflexion and anterior joint line swellin...
Anterior choroidal artery (AchA) syndrome is a rare entity characterized by the triad of hemiplegia, hemianaesthesia and contralateral hemianopia as a result of cerebral infarction in the anterior choroidal artery territory.
The syndrome may also be associated with neuropsychological disorders,...
Anti-GQ1b IgG antibody syndrome refers to a number of conditions which share autoantibodies to the ganglioside complex GQ1b, and have overlapping clinical spectrums.
The conditions believed to represent various clinical manifestations of a common immunological disorder include 1:
Antiphospholipid syndrome is a systemic autoimmune disorder. It is usually defined as the clinical complex of vascular occlusion and ischemic events occurring in patients who have circulating antiphospholipid antibodies.
Antiphospholipid syndrome is characterized by venou...
Pulmonary involvement in antiphospholipid syndrome is one of the most frequent arterial complications of antiphospholipid syndrome.
It is essentially related to pulmonary arterial microthrombosis and may cause a wide spectrum of conditions, which include 3-5:
Anti-synthetase syndrome (ASS) is a systemic, inflammatory, autoimmune disease that is characterized by inflammatory myositis, polyarthritis associated with interstitial lung disease (ILD) and anti-synthetase autoantibodies.
ASS can result from autoantibodies to eight of the aminoacy...
Antley-Bixler syndrome (ABS), also known as trapezoidocephaly-synostosis syndrome, is a rare autosomal dominant or recessive condition characterized by craniosynostosis and extra-cranial synostoses. Mid-facial hypoplasia is also common.
It is a very rare condition with only 50 cas...
Apert syndrome (also known as type I acrocephalosyndactyly) is a syndrome that is predominantly characterized by skull and limb malformations.
The estimated incidence is 1 case per 65-80,000 pregnancies.
increased paternal age has been proposed 6
Apical hypertrophic cardiomyopathy (AHCM or ApHCM), also known as Yamaguchi syndrome, is a rare form of hypertrophic cardiomyopathy which usually involves the apex of the left ventricle, rarely involves the right ventricular apex, or involves both apices.
Historically, this condit...
Asherman syndrome, also known as uterine synechiae, is a condition characterized by the formation of intrauterine adhesions, which are usually sequela from injury to the endometrium, and is often associated with infertility.
There is a tendency for the condition to develop soon af...
Asphyxiating thoracic dysplasia, also known as Jeune syndrome, is a type of rare short limb skeletal dysplasia, which is primarily characterized by a constricted long narrow thoracic cavity, cystic renal dysplasia and characteristic skeletal features. It is also sometimes classified as one of th...
Asplenia syndrome (also known as right isomerism or Ivemark syndrome) is a type of heterotaxy syndrome.
There is an increased male predilection. Asplenia syndrome is usually diagnosed in neonates 4.
In contrast to polysplenia syndrome, most patients die be...
Asymmetric ventriculomegaly, interhemispheric cyst and dysgenesis of the corpus callosum (AVID) is a triad of congenital cerebral anomalies.
markedly asymmetric enlargement of the lateral ventricles may be the initial finding on routine fetal morphology ultrasound.
Ataxia telangiectasia is a rare multisystem disorder which carries an autosomal recessive inheritance, sometimes classified as a phakomatosis. It is characterized by multiple telangiectasias, cerebellar ataxia, pulmonary infections and immunodeficiency.
On brain imaging, it usually demonstrate...
Athlete heart syndrome refers to adaptations in both cardiac structure and function seen in people engaged in high-performance and endurance physical exercise.
The prevalence of the condition has increased due to the increased popularity of recreational exercise, approx 3.6/100,00...
There are several autoinflammatory diseases with periodic fevers. These include
familial mediterranean fever (FMF)
cryopyrin-associated periodic syndrome (CAPS)
tumor necrosis factor receptor-associated periodic fever syndrome (TRAPS)
hyperimmunoglobulinemia D and periodic fever syndrome / m...
Autonomic dysreflexia (AD) is a life-threatening condition prevalent amongst patients with high spinal cord injury (SCI) and may occur any time after injury. It is a syndrome characterized by an exaggerated reflex increase in blood pressure, usually accompanied by bradycardia in response to a st...
Babinski-Nageotte syndrome is thought to be a brainstem stroke syndrome in between that of the hemimedullary syndrome (Reinhold syndrome) and the lateral medullary syndrome (Wallenberg syndrome) 1,2.
In many texts this eponymous syndrome is incorrectly used synonymously with hemim...
Bannayan–Riley–Ruvalcaba syndrome (BRRS or BRR syndrome) is a very rare autosomal dominant hamartomatous disorder caused by a mutation in the PTEN gene. It is considered in the family of hamartomatous polyposis syndrome.
There are no formal diagnostic criteria for this disease, but characterist...
Bardet-Biedl syndrome (BBS), previously known as the Laurence-Moon-Bardet-Biedl syndrome (LMBBS), is a rare autosomal recessive hereditary condition.
The clinical spectrum includes:
retinal anomalies: similar to that of retinitis pigmentosa
Barth syndrome (BTHS), also known as 3-methylglutaconic aciduria type II, is an extremely rare X-linked multisystem disorder that is usually diagnosed in infancy.
Barth syndrome has an estimated prevalence of 1 in 300,000-400,000 live births.
It is characte...
Bartter syndrome is a rare inherited renal disorder.
Bartter syndrome is characterized by hyperplasia of the juxtaglomerular cells along with:
elevated plasma renin
Beckwith-Wiedemann syndrome (BWS) is a congenital overgrowth disorder characterized by a unique set of features that can consist of:
macroglossia: most common clinical finding 4
otic dysplasia ref
localized gigantism / macrosomia
Benedikt syndrome, or paramedian midbrain syndrome, is a midbrain stroke syndrome that involves the fascicles of the oculomotor nerve and the red nucleus.
ipsilateral CN III palsy 1-4
crossed hemiataxia 1-4
crossed choreoathetosis 1-4
It is usually caused by...
Benign paroxysmal positional vertigo (BPPV) is one of the most common causes of vertigo. It occurs secondary to change in posture and typically is associated with nystagmus. The etiology is thought to be due to changes of position of the otoliths in the inner ear, most commonly into the posterio...
Bertolotti syndrome refers to the association between lumbosacral transitional vertebrae and low back pain.
Although it may be a consideration in younger patients, the entity is considered controversial and has been both supported and disputed since the Italian radiologist Mario Bertolotti (187...
Bile sump syndrome refers to a complication following a side-to-side choledochoduodenostomy.
This complication occurs in ~1% of patients following a side-to-side choledochoduodenostomy.
Recurrent abdominal pain, cholangitis, pancreatitis, or biliary obstr...
Birt-Hogg-Dubé (BHD) syndrome or folliculin gene-associated syndrome is a genetic multisystemic disease mainly characterized by:
multiple lung cysts and secondary spontaneous pneumothoraces
multiple bilateral renal tumors (particularly chromophobe renal cell cancer and oncocytoma)
Blue rubber bleb nevus syndrome (BRBNS) or Bean syndrome, is a rare sporadic syndrome characterized by multifocal venous anomalies. Patients often have multiple soft blue skin lesions associated with multiple bowel venous malformations, which could lead to lower gastrointestinal bleeding.
Bogorad syndrome also known as the syndrome of crocodile tears, is characterized by residual facial paralysis with profuse lacrimation during eating. This phenomenon is also known as paroxysmal lacrimation or the gustolachrymal reflex. It is caused by a misdirection of the regenerating autonomic...
Bone marrow edema syndrome of the foot and ankle, also known as transient bone marrow edema syndrome of the foot and ankle, refers to the presence of self-limited, patchy bone marrow T2 hyperintensities in the bones of the ankle and/or foot of unknown etiology. It is related to transient osteopo...
Börjeson-Forssman-Lehmann syndrome (BFLS) is an extremely rare disorder characterized by
gonadal failure (testes in males or the ovaries in females) to produce hormones (hypogonadism)
distinctive facial features.
Affected infants tend to experience ...
Bouveret syndrome refers to a gastric outlet obstruction secondary to impaction of a gallstone in the pylorus or proximal duodenum. Thus, it can be considered a very proximal form of gallstone ileus.
Bouveret syndrome occurs most commonly in elderly women. The presenting...
Branchio-oculo-facial syndrome (BOFS) is a very rare autosomal dominant genetic disorder that is characterized clinically by abnormalities affecting the eyes, craniofacial structures, and branchial sinuses.
More than 80 cases have been reported in the global literature since its f...
Brissaud-Sicard syndrome is a very rare pontine stroke syndrome that involves the anterolateral and inferior pons.
Classically, the syndrome presents as ipsilateral facial cramps and contralateral hemiparesis 1-3.
It has been postulated that the syndrome is ca...
Brown-Séquard syndrome, also known as hemicord syndrome, is the result of damage to, or impairment of, the left or right side of the spinal cord. It is characterized by a characteristic pattern of motor and sensory deficits that are determined by the decussation pattern of various white matter t...
The Brown syndrome refers to an inability of a patient to perform an upward gaze while the eye is adducted due to an abnormality of the superior oblique tendon sheath complex.
History and etymology
It was first described by Allan Brown in 1950 1.
A cardiac "channelopathy" resulting from mutations in genes coding for cardiac sodium (Na+) channels, the Brugada syndrome is a common cardiac cause of sudden death in patients with structurally normal hearts.
Age of diagnosis ranges from 2 days to 84 years old. It is estimated to...
Bruns syndrome occurs in patients with an obstructing intraventricular mass.It consists of abrupt paroxysms of:
The symptoms are characteristically exacerbated with sudden movements of the head.
There are two main theories as to the pathogenesis o...
Budd-Chiari syndrome, also known as hepatic venous outflow obstruction (HVOO), refers to the clinical picture that occurs when there is partial or complete obstruction of the hepatic veins. It is characterized on imaging by ascites, caudate hypertrophy, peripheral atrophy, and prominent collater...
Buried bumper syndrome (BBS) is a rare but important complication in patients with a percutaneous gastrostomy tube, occurring by migration of the internal bumper along its track. The tube may get lodged anywhere between the gastric wall and the skin and lead to life-threatening complications inc...
Buschke-Ollendorff syndrome (BOS), also known as disseminated dermatofibrosis lenticularis 2, comprises of osteopoikilosis associated with disseminated connective tissue and cutaneous yellowish nevi, predominantly on the extremities and trunk 1. Recent genetic work has linked this syndrome to ...
Caffey disease or infantile cortical hyperostosis is a largely self-limiting disorder which affects infants. It causes bone changes, soft-tissue swelling, and irritability.
It is distinct from physiological periostitis which can be seen involving the diaphyses of the tibiae, humeri, and femora ...
Campomelic dwarfism, also known as campomelic dysplasia, is a rare form of skeletal dysplasia.
Campomelic dwarfism is rare with an estimated incidence of ~1:200,000 births.
genital malformations: may be present in ~66% of patients 6
Camptocormia (bent spine syndrome or cyphose hystérique) is a rare syndrome characterized by involuntary flexion of the thoracolumbar spine with weight-bearing which reduces when laying down, and is due to isolated atrophy of the paraspinal muscles.
In a small case series (n=16), ...
Camptodactyly arthropathy coxa vara pericarditis (CACP) syndrome is a rare condition principally characterized by
congenital or early-onset camptodactyly and childhood-onset non-inflammatory arthropathy
coxa vara deformity or other dysplasia associated with progressive hip disease
Camurati-Engelmann disease, also known as progressive diaphyseal dysplasia, is a rare autosomal dominant sclerosing bone dysplasia. It begins in childhood and follows a progressive course.
Common symptoms include extremity pain, muscle weakness, cranial nerve impairment a...
Carcinoid syndrome refers to a spectrum of symptoms that result from excessive hormone (mainly serotonin) secretion.
Occurs equally between the sexes, most commonly in the 40-70 year age group 3.
Diarrhea is the most common and earliest symptom but others ...
Carney complex (not to be confused with the Carney triad) is a rare multiple endocrine neoplasia syndrome characterized by 1-4:
seen in two-thirds of patients with Carney complex
skin pigmentation (blue nevi): especially of the face, trunk, lips, and sclera
Carney-Stratakis syndrome is a rare autosomal dominant condition comprising of familial paraganglioma and gastric stromal sarcoma.
It is considered to be distinct from, but perhaps related to, the Carney triad 1. Neither should be confused with the unrelated Carney complex.
Carney triad is a rare syndrome defined by the coexistence of three tumors:
extra-adrenal paraganglioma (e.g. spinal paraganglioma)
initially, only functioning extra-adrenal paragangliomas were included, but subsequent work includes non-functioning extra-adrenal paragangliomas 1
Carotidynia, also known as Fay syndrome, is a rare syndrome characterized by neck pain in the region of the carotid bifurcation.
It was classified by the International Headache Society (IHS) in 1988 as an idiopathic neck pain syndrome associated with tenderness over the carotid bifurcation with...
Carpal tunnel syndrome results from compression of the median nerve within the carpal tunnel. It is a cause of significant disability and is one of three common median nerve entrapment syndromes, the other two being anterior interosseous nerve syndrome and pronator teres syndrome.
Carpenter syndrome, also called acrocephalopolysyndactyly type II (ACPS type II) is an extremely rare autosomal recessive congenital disorder.
It is characterized by a number of features which include:
Cauda equina syndrome is considered an incomplete cord syndrome, even though it occurs below the conus, and refers to a collection of symptoms and signs that result from severe compression of the descending lumbar and sacral nerve roots. It is most commonly caused by an acutely extruded lumbar d...
Caudal regression syndrome represents a spectrum of structural defects of the caudal region. Malformations vary from isolated partial agenesis of the coccyx to lumbosacral agenesis.
Caudal regression syndrome is rare, with an estimated incidence of 1:7500-100,000 7,10.
The vast m...
Cavernous sinus syndromes refer to constellations of clinical signs and symptoms referable to pathology within or adjacent to the cavernous sinus.
Patients present with multiple unilateral cranial neuropathies involving any combination of the following:
Cavitary mesenteric lymph node syndrome is seen in association with celiac disease and is characterized by the triad of:
low-attenuation lymphadenopathy that sometimes contains fat-fluid levels
CEC syndrome refers to the combination of celiac disease, epilepsy and bilateral occipital calcifications. This is also known as Gobbi syndrome. Patients with cerebral calcifications and celiac disease without epilepsy are considered as having an incomplete form of CEC syndrome 1.
Central cord syndrome is the most common type of incomplete spinal cord syndrome, usually the result of trauma, accounting for ~10% of all spinal cord injuries. As the name implies, this syndrome is the result of a damage to the central portion spinal cord and in the setting of trauma most commo...
Cerebellar ataxia with neuropathy and vestibular areflexia syndrome (CANVAS) is a rare neurodegenerative balance disorder characterized by cerebellar ataxia, sensory neuronopathy (ganglionopathy), and bilateral vestibular hypofunction.
The epidemiology is yet to be defined, but CA...
Cerebellar mutism syndrome usually develops after resection of midline cerebellar or intraventricular tumors in the posterior fossa. Typical features of this condition are transient mutism, ataxia, hypotonia, and irritability.
The nomenclature of this syndrome has considerable conf...