[CASE-STUDY] Infantile histiocytoid Sweet syndrome without an underlying systemic association, OCT 2021

[Shell567]

"Pediatric Sweet syndrome is rare, accounting for an estimated 5% to 8% of all Sweet syndrome cases. Pediatric HSS (histiocytoid Sweet's syndrome) is a histopathologic variant that is even more uncommon, with only 5 previous cases documented and all infantile cases having an identifiable underlying systemic association."

"Halpern et al reported that children with Sweet syndrome over 3 years of age were more likely to have an associated hematologic malignancy, whereas finding no predilection for either sex, whereas children under 3 with Sweet syndrome were predominantly male and had no associated malignancy. Preceding infection and underlying hematologic malignancy are the most common associated findings with Sweet syndrome in children."

"HSS has been associated with postinflammatory scarring, acquired cutis laxa, cardiovascular compromise, epiglottitis, gastrointestinal bleeding, and skin necrosis. Of these, cardiovascular sequelae, which include pericarditis, vessel dilation, valve disease, and myocardial infarction are the most severe and associated with the highest risk of mortality in the pediatric population."

- 11-month-old boy with a 3-month history of relapsing fevers ranging from 37.7 °C to 38.6 °C.

- Irritability and tender skin eruptions recurring every 5 to 6 days.

- Diagnosed with histiocytoid Sweet's syndrome. No underlying condition.

- Responded well to a 6-week course of oral prednisolone solution at a dose of 2.0 mg/kg/d.

ADDITIONAL NOTES:

HISTIOCYTOID SWEET'S SYNDROME.

In SS, mature white blood cells called neutrophils accumulate in the tissues. In HSS, immature myeloperoxidase-positive cells and not mature neutrophils can be seen. Myeloperoxidase is an enzyme that’s abundantly expressed in neutrophils.

The immature cells in HSS can be mistaken for histiocytes; immune cells that destroy foreign substances and help fight infection. Sometimes, real (authentic) histiocytes may also be present. ncbi.nlm.nih.gov/pmc/articl...

[SweetsBoy21]

My son, 2 at the time was dx with HSS. Unfortunately, after months of typical treatment (prednisone,dapsone, etc.) he wasn't responding as expected and we found out that he did have MDS. He's 3 now and just had a bone marrow transplant 2 months ago.

[Shell567 Administrator Sweet's Syndrome UK in reply to SweetsBoy21]

Sorry to hear that your little one is so ill, SweetsBoy21. Wishing you and your son all the best.

[Shell567 Administrator Sweet's Syndrome UK]

PAEDIATRIC SWEET'S SYNDROME.

Sweet syndrome of childhood with acquired cutis laxa (Marshall syndrome) as primary manifestation of Takayasu arteritis, 2022.

ARTICLE IN GERMAN. USE TRANSLATE.

"The present case describes a childhood Sweet's syndrome with postinflammatory elastolysis and acquired cutis laxa as the initial diagnosis of childhood Takayasu's arteritis."

"Childhood Sweet's syndrome with postinflammatory elastolysis and acquired cutis laxa represents a potential cutaneous warning sign for life-threatening cardiovascular complications such as aortitis, aortic aneurysm, coronary artery stenosis, and heart failure. While Sweet's syndrome in adults heals without scarring, some children show residual wrinkled healing of the Sweet's lesions. Such an acquired cutis laxa without a genetic background has been described in 10 children so far, of which 6 children had conspicuous changes in the aorta (aortitis, aneurysms), the outgoing large vessels and the heart. We report a child in whom Sweet's syndrome, which resolved with postinflammatory elastolysis, led to the diagnosis of Takayasu's arteritis."

- Paediatric Sweet's syndrome is very rare. "Only 8% of all Sweet syndromes occur in childhood."

- This article states that scarring doesn't occur in adults. In some adults there can be scarring/post-inflammatory hyperpigmentation.

- Elastolysis: loss of elastic fibres in skin.

- In children, cutis laxa, also known as generalised elastolysis, can develop secondary to Sweet's syndrome. This condition is characterised by loosely hanging skin that lacks any elasticity.

- "A special feature of Sweet's syndrome in childhood is the optional healing in the form of post-inflammatory elastolysis with acquired cutis laxa, which is named Marshall's syndrome after the person who first described it."

- "Cutis laxa is a warning sign for life-threatening cardiac complications such as aortitis (such as Takayasu's arteritis), aortic aneurysms, coronary artery stenosis and heart failure."

-Takayasu's arteritis: an autoimmune condition that causes inflammation of the main blood vessel that carries blood from the heart to the rest of the body (aorta) and its associated branched blood vessels.

- "Sweet's syndrome may precede cardiac manifestation or, as in our case, be a primary manifestation." Sweet's syndrome secondary to Takayasu's arteritis.

- "...the Marshall syndrome, manifests itself more frequently in children and is limited to the pre-existing lesions, mainly after neutrophil-rich inflammation. The loss or fragmentation of elastic fibers is probably based on excessive elastase release from neutrophilic granulocytes and macrophages or a dysfunction of elastase inhibitors. This phenomenon has been described in particular in connection with Sweet's syndrome, also in the context of Takayasu's arteritis."

- "Affected children with Sweet's syndrome and post-inflammatory elastolysis should be promptly examined cardiologically and rheumatologically in order to prevent a complication of vascular involvement through early anti-inflammatory and immune-modulating systemic therapy." ncbi.nlm.nih.gov/pmc/articl...

[Shell567 Administrator Sweet's Syndrome UK in reply to Shell567]

CUTIS LAXA, DERMNET NZ dermnetnz.org/topics/cutis-...

[Shell567 Administrator Sweet's Syndrome UK in reply to Shell567]

Takayasu Arteritis, Vasculitis UK vasculitis.org.uk/about-vas...