Brain malformations in diprosopia observed in clinical cases, museum specimens and artistic representations.

BACKGROUND: Diprosopus is a rare malformation of still unclear aetiology. It describes a laterally double faced monocephalic and single-trunk individual and has to be distinguished from the variant Janus type diprosopus. RESULTS: We examined seven double-faced foetuses, five showing true diprosopus, and one each presenting as monocephalic Janiceps and parasitic conjoined twins. Four of the foetuses presented with (cranio)rachischisis, and two had secondary hydrocephaly. Three foetuses showed cerebral duplication with concordant holoprosencephaly, Dandy-Walker cyst and/or intracranial anterior encephalocele. In the Janiceps twins, cerebral duplication was accompanied by cerebral di-symmetry. In the parasitic twins the cyclopic facial aspects were suggestive of concordant holoprosencephaly. In one of the true diprosopus cases, pregnancy was achieved after intracytoplasmic sperm injection. Whole-exome sequencing, perfomed in one case, did not reveal any possible causative variants.The comparison of our double-faced foetuses to corresponding artistic representations from the Tlatilco culture allowed retrospective assignment of hairstyles to brain malformations. CONCLUSION: Brain malformations in patients with diprosopus may not be regarded as an independent event but rather as a sequel closely related to the duplication of the notochord and neural plate and as a consequence of the cerebral and associated craniospinal structural instabilities.

Distal Arthrogryposis with Impaired Proprioception and Touch: Description of an Early Phenotype in a Boy with Compound Heterozygosity of PIEZO2 Mutations and Review of the Literature.

The recessive PIEZO2-associated disease, distal arthrogryposis with impaired proprioception and touch (DAIPT), is characterized by hypotonia, perinatal respiratory distress, significantly delayed motor milestones, and progressive symptoms of distal arthrogryposis and scoliosis. Here, we describe the youngest patient with DAIPT to date, who, at the age of 3.5 years, did not show a single clinical sign of distal arthrogryposis or contractures, but had a history of bilateral clubfoot operations. On the contrary, he presented with some features, not described thus far, such as syringohydromyelia, a small cyst of the spinal cord, moderate microcephaly with premature closure of anterior fontanelle, and spontaneous unilateral patella dislocation at the age of 32 months. Using whole exome sequencing, we identified 2 new different loss-of-function mutations in the PIEZO2 gene in our patient. We also review the phenotypes of all 16 previously published patients with DAIPT, summarize the distinctive clinical features of this rare genetic disorder, and recommend that DAIPT be included in the differential diagnosis of floppy infant. PIEZO2 is a unique ion channel that converts mechanical impulses into cellular signals and is involved in various mechanotransduction pathways. In addition to DAIPT, mutations in PIEZO2 have been described to cause 3 more distinct phenotypes of distal arthrogryposis, which are dominant and associated with gain-of-function mutations. On the contrary, recessive DAIPT is associated with loss-of-function PIEZO2 mutations.

[Life threatening secondary bacterial infection of varicella skin lesions]. / Lebensbedrohliche bakterielle Infektionen ausgehend von Varizellen Hautläsionen.

As immunization coverage of varicella vaccination is low, the disease is still very frequent in Austria. Albeit the prognosis in general is good, the incidence of varicella-related hospitalization is about 6 per 100,000 in all children between 0-15 years of age, affecting mainly previously healthy children. Especially young children under the age of 5 are at risk with highest rates among children younger than one year. The most common complications are secondary bacterial infections, neurological and respiratory complications. Two cases of life threatening secondary bacterial infection are presented. One child suffered from a Toxic Shock Syndrome caused by group A streptococcus along with large necrotizing skin lesions. The second child nearly lost her left eye due to a deep orbital abscess. Both children survived without severe sequelae but had to undergo several procedures of plastic surgery. Implementation of the varicella vaccination program in the USA has shown a near elimination of deaths due to severe varicella complications. The initiation of the varicella vaccination program for children until the age of 2 in Austria should be considered to prevent complications and deaths caused by varicella.