≤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 dist...
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 5,000 live births. It is the most common termina...
4D syndrome is a term used to describe a manifestation of syndromic glucagonoma, 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 re...
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 characterized by anemia and skeletal deformity.
Aase-Smith syndrome has a prevalence of less than 1 per 1,000,000 persons. There have only been 20 reported cases.
Abdominal compartment syndrome (ACS) is a disease defined by the presence of new end-organ dysfunction secondary to elevated intraabdominal pressure (IAP). Radiological diagnosis is difficult and usually suggested when a collection of imaging findings are present in the appropriate clinical sett...
Abdominal migraine is a syndrome that presents as recurrent episodes of severe paroxysmal abdominal pain, coupled with vasomotor symptoms, nausea, and emesis that lasts for at least 1 hour 3. Historically it has tended to be a pediatric diagnosis, but it is now increasingly seen in adults. It is...
Ablepharon macrostomia syndrome is a very rare genetic disorder characterized by macrostomia, wide mouth and microblepharon.
A few of the clinical features of this syndrome are:
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 describes the presentation of patients with one of a number of life-threatening aortic pathologies that give rise to similar clinical presentations.
Exactly which entities are included under the umbrella term acute aortic syndrome varies somewhat from publication to public...
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 motor axonal neuropathy (AMAN) is characterized as progressive symmetrical flaccid paralysis with areflexia. It is a pure motor axonopathy and is a variant of Guillain-Barré syndrome.
In 1991, a short-lived epidemic of Guillain-Barré syndrome (GBS) was seen in Northern China....
Acute respiratory distress syndrome (ARDS) is a form of acute lung injury 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.
This is a disti...
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. It may be accompanied by orofacial and cardiac malformations 6.
polymicrogyria: can be associated with a...
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:
Agraphia represents acquired impairments of writing ability secondary to damage or dysfunction of the central nervous system. Impairments caused solely by motor dysfunction (e.g. hand paresis or tremor) are not considered to be forms of agraphia 1.
Agraphia is rarely an i...
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 (also known as arteriohepatic dysplasia) is a congenital genetic multisystem 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 inhe...
Alexia (or acquired dyslexia) is a neurological term refers to an acquired impairment of reading resulting from damage of critical brain areas.
Alexia can manifest itself as an impairment of oral reading and reading comprehension alike and can occur in combination with va...
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 agenesis of an 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 incid...
Amniotic band syndrome (ABS) comprises 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.
The phenomenon ...
Androgen insensitivity syndrome (AIS), also known as the testicular feminization 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.
Common in soccer players and ballet dancers 1.
Clinical features of anterior ankle impingement syndrome include pa...
Anterior choroidal artery syndrome is a rare entity characterized by the triad of
This occurs as a result of cerebral infarction in the anterior choroidal artery territory.
The syndrome may also be associated with neuropsychological di...
Anterior resection syndrome refers to wide spectrum of symptoms which develop post-sphincter preserving rectal resection for rectal cancer.
Pelvic radiotherapy is a known risk factor to develop anterior resection syndrome.
There have been reports that up to 47% of patients who un...
Anterior suprapatellar (quadriceps) fat pad impingement syndrome is a rare cause of anterior knee pain although anterior suprapatellar fat pad edema may often, and possibly more commonly, be incidental 1,2.
The anterior suprapatellar fat pad is enlarged with mass e...
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.
Anti-synthetase syndrome can result from autoantibodies to...
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...
Arterial tortuosity syndrome (ATS) is a very rare autosomal recessive connective tissue disease. It is similar to Ehlers-Danlos syndrome (EDS), the major differentiator being the general tortuous nature of the larger arteries.
It presents similarly to other collagen disor...
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.
severe/complex congenital heart disease (50%), especially cyanotic ...
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 that 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...
Atelosteogenesis refers to a heterogeneous group of lethal skeletal dysplasias that are characterized by aplasia/hypoplasia of the humeri, femora and spine.
atelosteogenesis type I (boomerang dysplasia)
atelosteogenesis type II
atelosteogenesis type III 4
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...
Auriculocondylar syndrome is a rare congenital syndrome primarily characterized by malformed ears and mandibular condyle aplasia/hypoplasia.
This is an autosomal dominant genetic disease resulting from GNAI3 or PLCB4 gene defects. This affects facial development especially the 1st an...
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...
Bálint syndrome is characterized by:
simultanagnosia (inability to perceive more than one object at a time)
It typically results from damage to the parieto-occipital regions, and has been associated with 1-3:
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...
Bannayan-Zonana syndrome, also known as Bannayan-Riley-Ruvalcaba syndrome, is a rare hamartomatous disorder.
Male predominance is reported 1.
Bannayan-Zonana syndrome is characterized by:
Other findings that...
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), recently reclassified as Beckwith-Wiedemann spectrum, is a congenital overgrowth disorder characterized by a unique set of features that can consist of:
macroglossia: most common clinical finding 4
ear pits or creases
localized gigantism / macr...
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...
Big black brain is a radiologic pattern unique to infants and toddlers in the context of traumatic brain injury, most frequently due to abusive head trauma.
The CT presentation is a parenchymal hypodensity and uniform loss of gray-white differentiation in the entire hemisphere, associated with...
Bile plug syndrome, also known as inspissated bile syndrome, is an uncommon cause of jaundice in neonates. Refers to a rare extrahepatic mechanical obstruction of the major bile duct in the perinatal period caused by viscous bile (sludge) within its lumen 3.
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...
Bing-Neel syndrome is an extremely rare neurological complication of Waldenström macroglobulinemia where there is malignant lymphocyte infiltration into the central nervous system (CNS).
The exact incidence is unknown, however, in one study of patients with Waldenström macroglobul...
Birt-Hogg-Dubé syndrome (BHDS), also known as folliculin gene-associated syndrome, is a multi-system disease characterized by:
cutaneous manifestations, typically fibrofolliculomas
multiple lung cysts and spontaneous pneumothoraces
increased risk of renal tumors, typically chromophobe oncocyt...
Blueberry muffin syndrome (a.k.a. blueberry muffin baby or rash) refers to a skin appearance seen in pediatric patients with multiple raised cutaneous, classically blue/purple lesions which is due to extramedullary hematopoiesis in the dermis.
The syndrome was originally described in congenital...
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 (blueberry muffin syndrome) associated with multiple bowel venous malformations, which could lead to lower gastr...
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 refers to a group of transient, self-limiting clinical entities of unknown cause, which are associated with the presence of bone marrow edema pattern.
These conditions include:
transient osteoporosis of the hip
bone marrow edema syndrome of the foot and ankle
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...
Branchio-otic syndrome (also known as BOS, BOS1, BO syndrome 1 and branchiootic dysplasia) is a rare autosomal dominant disease. It manifests as abnormalities of the second branchial arch, with predominant abnormalities of the ear. No renal disease is seen, in contradistinction to its close name...
Branchio-oto-renal (BOR) dysplasia, syndrome, or spectrum disorder is a rare syndromic disorder characterized by cervical branchial apparatus anomalies, ear malformations, and renal anomalies. If there are no renal anomalies, then it is more likely to be branchiootic dysplasia.
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...
Brown syndrome refers to a failure of upward gaze while the eye is adducted secondary to an abnormality of the superior oblique tendon sheath complex.
This abnormality is a little counter-intuitive and highlights how the action of the superior oblique is position-dependent and that e...
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 and 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 ...
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.
There is no clear consensus regarding the number of occluded veins, some authors claim that there should...
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 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 bot...
Cachexia is a syndrome of metabolic dysfunction secondary to an underlying disease in which there is depleted skeletal muscle (sarcopenia) which may or may not be accompanied by an absolute loss of body fat.
Cancer cachexia is specifically used to refer to the cachexia associated ...