Microvascular changes on nailfold capillaroscopy in acute stage of Kawasaki disease: a new diagnostic paradigm for an enigmatic condition.

OBJECTIVES: Kawasaki disease (KD) is a medium vessel vasculitis with a predilection to involve coronary arteries. However, there is a paucity of literature on microvascular changes in patients with KD. METHODS: Children diagnosed with KD based on American Heart Association guidelines 2017 were enrolled prospectively. Demographic details and echocardiographic changes in coronaries were recorded. Nailfold capillaries were assessed using Optilia Video capillaroscopy and data were analysed using Optilia Optiflix Capillaroscopy software at acute (prior to IVIG administration) and subacute/convalescent phase. RESULTS: We enrolled 32 children with KD (17 boys) with a median age of 3 years. Nailfold capillaroscopy (NFC) was performed in 32 patients in the acute phase (compared with 32 controls) and in 17 during the subacute/convalescent phase at a median follow-up of 15 (15-90) days after IVIG treatment. The following findings were seen in NFC in the acute phase of KD: reduced capillary density (n = 12, 38.6%), dilated capillaries (n = 3, 9.3%), ramifications (n = 3, 9.3%) and capillary haemorrhages (n = 2, 6.2%). Capillary density was reduced significantly in the acute phase of KD (38.6%) as compared with the subacute/convalescent phase (25.4%) (P-value <0.001) and controls (0%) (P-value = 0.03). We observed no correlation between coronary artery involvement and mean capillary density (P = 0.870). CONCLUSION: Results show that patients with KD have significant nailfold capillary changes in the acute phase. These findings may provide a new diagnostic paradigm for KD and a window to predict coronary artery abnormalities.

The neuroanatomical and neurovascular organization of normal fetal hypothalamic explants in the third cerebral ventricle of Brattleboro rats with homozygous diabetes insipidus.

This investigation has combined microangiography, immunocytochemistry, coupled with transmission and scanning electron microscopy to discuss the neuroanatomical interactions that occur in the brains of Brattleboro rats with diabetes insipidus, following stereotaxic placement of normal fetal hypothalamic fragments into the third cerebral ventricle. Following surgical placement of 17 day post-coitus hypothalamic fragments, host rats with chronic autosomal homozygous diabetes insipidus were killed and their brains were prepared for analysis. A significant degree of explants (68%) flourished and grew in the lumen of the third cerebral ventricle of recipient hosts. Explants were rapidly invaded by host vessels from two routes. Vessels arose from the underlying mantle plexus of portal capillaries which remained fenestrated in the lower one-third of the explants and developed neurovascular (neurohemal) zones. The second source of vessels arose from bed capillaries of the adjacent paraventricular nucleus and adjacent hypothalamus. In contrast to vessels arising from the contact zone, these latter vessels remained unfenestrated. Small clusters of immunocytochemically positive neurons (neurophysin positive) were seen throughout the explants. Numerous healthy magnocellular neurons harboring numerous dense core vesicles and exhibiting multiple axosomatic and axodendritic synapses were seen throughout the neuropil of explants. Axon profiles were noted to terminate upon the abluminal basal lamina of perivascular spaces surrounding fenestrated capillaries in the lower one third of explants. None of the host animals exhibited physiological return to normal parameters of urine output, drinking behavior, and/or urine osmolarity. However the growth and development of explants in the third cerebral ventricle of DI hosts coupled with the emergence of bonafide neurovascular zones supports a potential anatomical substrate for the central delivery of neuropeptide hormones in this experimental model.