Idiopathic calcinosis cutis in an infant: The importance of a wait-and-see approach.

A healthy 2-year-old girl presented with multiple asymptomatic subcutaneous nodules on both legs. Histologically demonstrated calcium deposition within the dermis and subcutaneous tissue consistent with calcinosis cutis. Laboratory abnormalities, underlying genetic conditions, and potential triggering factors were ruled out. The lesions resolved over an 18-month period without treatment, emphasizing the importance of the wait-and-see approach in idiopathic cases of calcinosis cutis.

Generalized Lymphatic Anomaly as a Differential Diagnosis of Lytic Lesions.

Generalized lymphatic anomaly (GLA) is an infrequent multiorgan disease characterized by the presence of abnormal proliferation of lymphatic vessels. The diagnosis requires histological confirmation, and the treatment is controversial. We are presenting a case of a 28-year-old male patient who was diagnosed with an extragonadal mediastinal nonseminomatous germ cell tumor. He underwent chemotherapy, and during this treatment, radiologic findings evidenced lytic lesions. Multiple biopsies were performed, which revealed the presence of abnormal lymphatic vessels, characteristic of GLA. There are different etiologies of osteolytic lesions, and on some occasions, they mimic a tumoral entity. The clinical suspicion of GLA is the first step in approaching the diagnosis, particularly in young adult patients.

The 5th edition of the World Health Organization Classification of Haematolymphoid Tumours: Myeloid and Histiocytic/Dendritic Neoplasms.

The upcoming 5th edition of the World Health Organization (WHO) Classification of Haematolymphoid Tumours is part of an effort to hierarchically catalogue human cancers arising in various organ systems within a single relational database. This paper summarizes the new WHO classification scheme for myeloid and histiocytic/dendritic neoplasms and provides an overview of the principles and rationale underpinning changes from the prior edition. The definition and diagnosis of disease types continues to be based on multiple clinicopathologic parameters, but with refinement of diagnostic criteria and emphasis on therapeutically and/or prognostically actionable biomarkers. While a genetic basis for defining diseases is sought where possible, the classification strives to keep practical worldwide applicability in perspective. The result is an enhanced, contemporary, evidence-based classification of myeloid and histiocytic/dendritic neoplasms, rooted in molecular biology and an organizational structure that permits future scalability as new discoveries continue to inexorably inform future editions.

Neonatal Generalized Lymphatic Anomaly with Skin Involvement.

Generalized lymphatic anomaly (GLA) is a rare congenital disorder of lymphatic development, presenting with multiple lymphatic malformations in different organs and tissues. Here, we present a case of a female neonate prenatally diagnosed with foetal hydrops and a mediastinal cystic lymphatic malformation that showed postnatal expansive and infiltrative growth into the major airways, compromising mechanical ventilation and further management of the neonate. Complications that arose during surgical treatment of mediastinal structures led to the patient's death. Lymphatic malformations were also noted in the skin at birth. Furthermore, a skin biopsy performed immediately after birth and the autopsy revealed an extremely rare diagnosis of combined macrocystic and microcystic forms of GLA with skin involvement.

Conradi-Hünermann-Happle syndrome with minimal signs.

A 4-year-old girl presented with congenital patches of scalp alopecia, which on physical examination, was consistent with blaschkolinear alopecic patches with mild epidermal atrophy. Similar atrophic hypopigmented patches were seen on the trunk and proximal extremities. With the clinical suspicion of Conradi-Hünermann-Happle syndrome, genetic testing was performed and revealed a mutation in the EBP gene. Despite characteristic cutaneous findings, no skeletal, ocular, or other anomalies were found on further evaluation.

Venous Malformations in Childhood: Clinical, Histopathological and Genetics Update.

Our knowledge in vascular anomalies has grown tremendously in the past decade with the identification of key molecular pathways and genetic mutations that drive the development of vascular tumors and vascular malformations. This has led us to better understand the pathogenesis of vascular lesions, refine their diagnosis and update their classification while also exploring the opportunity for a targeted molecular treatment. This paper aims to provide an overview of venous malformations (VM) in childhood. Specific entities include common VMs, cutaneo-mucosal VM, blue rubber bleb nevus syndrome or Bean syndrome, glomuvenous malformation, cerebral cavernous malformation, familial intraosseous vascular malformation and verrucous venous malformation. The clinicopathological features and the molecular basis of each entity are reviewed.

Diffuse reticulate purpura in two adolescents with anorexia nervosa and severe malnutrition.

Anorexia nervosa is an eating disorder frequently associated with cutaneous manifestations. A rare type of purpura, known as diffuse reticulate purpura, has been described in patients with anorexia nervosa and severe malnutrition. Typical characteristics of this condition include a purpuric reticulate rash predominantly affecting the trunk that rapidly resolves with adequate feeding. We report two male adolescent patients with anorexia nervosa and severe malnutrition who developed diffuse reticulate purpura.

Pigmented purpuric dermatosis in an infant.

Pigmented purpuric dermatoses (PPDs) are a group of idiopathic, chronic, and self-resolving conditions easily recognizable in adults but extremely uncommon in infants. We present the youngest patient with PPD reported to date.

Penile and scrotal infundibular cysts in an adolescent treated with sorafenib.

Sorafenib is a multikinase inhibitor increasingly used for the treatment of several solid tumors. Different types of keratotic lesions, such as squamous cell carcinoma, actinic keratosis, or infundibular cyst, have been reported in association with this therapy. We present a 15-year-old male diagnosed with desmoid fibromatosis who developed multiple penile and scrotal infundibular cysts while receiving treatment with sorafenib.

Telangiectasia-ectodermal dysplasia-brachydactyly-cardiac anomaly syndrome is caused by de novo mutations in protein kinase D1.

BACKGROUND: We describe two unrelated patients who display similar clinical features including telangiectasia, ectodermal dysplasia, brachydactyly and congenital heart disease. METHODS: We performed trio whole exome sequencing and functional analysis using in vitro kinase assays with recombinant proteins. RESULTS: We identified two different de novo mutations in protein kinase D1 (PRKD1, NM_002742.2): c.1774G>C, p.(Gly592Arg) and c.1808G>A, p.(Arg603His), one in each patient. PRKD1 (PKD1, HGNC:9407) encodes a kinase that is a member of the protein kinase D (PKD) family of serine/threonine protein kinases involved in diverse cellular processes such as cell differentiation and proliferation and cell migration as well as vesicle transport and angiogenesis. Functional analysis using in vitro kinase assays with recombinant proteins showed that the mutation c.1808G>A, p.(Arg603His) represents a gain-of-function mutation encoding an enzyme with a constitutive, lipid-independent catalytic activity. The mutation c.1774G>C, p.(Gly592Arg) in contrast shows a defect in substrate phosphorylation representing a loss-of-function mutation. CONCLUSION: The present cases represent a syndrome, which associates symptoms from several different organ systems: skin, teeth, bones and heart, caused by heterozygous de novo mutations in PRKD1 and expands the clinical spectrum of PRKD1 mutations, which have hitherto been linked to syndromic congenital heart disease and limb abnormalities.

Plaque-like cutaneous mucinosis of childhood.

A healthy 10-year-old boy presented with plaque-like cutaneous mucinosis (PCM) on his back. Cutaneous biopsy was followed by progressive resolution of the skin lesion. Pediatric PCM could differ clinically from the adult form. However, more cases are necessary to draw conclusions.

Suspected COVID-19-related reticulated purpura of the soles in an infant.

A growing number of skin lesions during the COVID-19 pandemic are being recognized. Acral ischemic lesions identical to chilblains are most typical in children and young adults. We report an infant girl, aged 1 month and 29 days, with a peculiar reticulated purpuric eruption on her soles, with positive immunohistochemistry for SARS-CoV-2 in the endothelia of dermal blood vessels. The patient had an excellent outcome without specific therapy.

Erythema multiforme-like lesions in children and COVID-19.

During examination of cases of chilblains in children and adolescents, we identified four patients who also showed skin lesions similar to erythema multiforme (EM). They had no other known triggers for EM. One of them had a positive PCR for SARS-CoV-2, while the other three were negative. Skin biopsies from two patients showed features not typical of EM, such as deep perivascular and perieccrine infiltrate and absence of necrosis of keratinocytes. Immunohistochemistry for SARS-CoV/SARS-CoV-2 spike protein showed granular positivity in endothelial cells and epithelial cells of eccrine glands in both biopsies. All patients had an excellent outcome, and had minimal or no systemic symptoms. The coincidence of EM, a condition commonly related to viruses, and chilblains in the setting of COVID-19, and the positivity for SARS-CoV/SARS-CoV-2 spike protein by immunohistochemistry strongly suggest a link between EM-like lesions and SARS-CoV-2.