Polyarteritis Nodosa and Kawasaki Disease (Medium Vessel Vasculitis) - Symptoms, pathophysiology

Polyarteritis Nodosa and Kawasaki Disease (Medium Vessel Vasculitis) – Symptoms, pathophysiology



hello in this video we're going to talk about medium vessel vasculitis vasculitis is inflammation of the blood vessels resulting in damaged vessels which can lead to potential complications such as organ ischemia as well as aneurysms primary vascular Lydda teas are classified into the size of the blood vessels affected large vessel vasculitis medium vessel vasculitis and small vessel vasculitis the medium vessel vasculitis includes polyarteritis nodosa and Kawasaki disease polyarteritis nodosa is a rare systemic necrotizing vasculitis targeting medium sized arteries polyarteritis nodosa has distinct features with particular involvement of the renal and visceral arteries it is associate with hepatitis B virus mononeuritis multiplex and renal infarction there is no involvement of the lungs if Sinha fills are usually normal and there is absence of anti neutrophilic cytoplasmic antibodies pathology of polyarteritis nodosa is characterized by focal and segmental transmural necrotizing inflammation which is essentially inflammation on all the layers of the blood vessel a pan artritis the exact etiology is unknown but possibly infection and because of its association with hepatitis B virus this could be the potential trigger from whatever antigen an antigen presenting cell can activate t-cells which will in turn stimulate the immune response in polyarteritis nodosa likely the cell mediated immune response is stimulated which involved the macrophages and the neutrophils in the acute phase of the disease neutrophils infiltrate all layers of the blood vessels causing damage to the surrounding tissue macrophages will then move in to clean up the area repairment of the vessel wall begins there is platelet plug formation as well as fibrin deposition collagen gets deposited as the vessel is repaired the segment of blood vessels here become fibrous this area is now termed fibrin or necrosis which is a special histopathological term seen in blood vessel necrosis and this is where segmental transmural necrotizing inflammation comes in there is necrosis of the vessel in segments fibrin or necrosis include dead cells and dead immune cells collagen proteins and fibrin the vessel is now not as strong aneurysms can occur aneurysms are dilatations are of up to one centimeter in size along the involved arteries and this is characteristic of polyarteritis nodosa at a macroscopic view blood vessels look like beads on a string polyarteritis nodosa commonly involves bifurcation and branching of the arteries during the healing process lumen narrowing can occur thanks to a number of factors thrombosis and fibrin deposition collagen deposition and hypertrophy of the smooth muscle layers the association with hepatitis B virus is because patients with hepatitis B can often present with polyarteritis nodosa so what is the clinical features of polyneuritis nodosa clinical features of polyarteritis nodosa are nonspecific symptoms such as fevers myalgia weight loss and a rash nervous system involvement is common with peripheral neuropathy and mononeuritis multiplex being the most common mononeuritis multiplex also called multiple mono neuropathy refers to an anatomical pattern of peripheral neuropathy that affects two or more at different nerves basically it's thought to be due to inflammation and occlusion of the Vaser nerve Wharram the blood vessel that actually supplies the nerves another feature of polyarteritis nodosa is the involvement of the renal artery which can lead to renal infarction and this is just due to inflammation of the blood vessel also the renal artery involved can lead to hypertension secondary to the renin-angiotensin-aldosterone system being activated important to mention that the risk of cardiovascular morbidity and mortality is high in polyarteritis nodosa and requires close monitoring the rush in polyarteritis nodosa can be numerous things including a purpura crash subcutaneous nodules Bullis of vesicular lesions and lovino reticularis there is also GI involvement characterized by nonspecific abdominal pain up to 50% of cases the investigations to order for someone suspected of polyarteritis nodosa includes a viral hepatitis serology full blood count and EU C's electrolyte urea cranny to check renal function diagnosis of polyarteritis nodosa is through a biopsy but in the absence of an easily accessible tissue for biopsy the arterial graphic demonstration of involve vessels particularly in the form of aneurysms of the small and medium-sized arteries in the renal hepatic and visceral vasculature is sufficient to make the diagnosis here's an image of an angiogram showing the renal artery supply note the small aneurysms throughout the medium-sized vessels the classic polyarteritis nodosa should be treated with a combination of steroids glucocorticoids and cyclophosphamide the treatment of hepatitis B virus associated polyarteritis nodosa involves a different approach prognosis of untreated patients is poor and mainly due to gastrointestinal complications and cardiovascular complications mentioned earlier important to know about another condition called cutaneous polyarteritis nodosa whereas classic systemic polyarticular so commonly affects you know the kidneys muscles nerves and GI tract as well as the skin vasculitis in the in cutaneous polyarteritis nodosa is skin limited the other type of medium-sized vasculitis is Kawasaki disease Kawasaki disease is an uncommon systemic vasculitis disease affecting mainly children under the age of five Kawasaki disease is a medium-sized vasculitis Kawasaki disease and henoch-schonlein purpura are the most common primary vascular disease in children it is more prevalent in Asians and Native Pacific Islanders and as a leading cause of childhood acquired heart disease in developed countries which include coronary aneurysms the exact cause of Kawasaki disease is unknown but clinical and epidemiological data support infectious cause in Kawasaki disease and intense inflammatory cell response develops in a wide array of organs and tissues in medium-sized arteries such as the coronary arteries the pathophysiology of kawasaki involves monocytes IgE antibodies neutrophils in the acute setting and sorrow toxic t-cells these guys all play a role in the inflammation of the medium-sized vessel what is thought to drive this temporary vasculitis is an infection theories include our Staphylococcus and streptococcus species such as from strep throat and even a viral infection antigen presenting cells will pick up these antigens and mount an inflammatory response the inflammatory response somehow misdirects the attack and will attack the medium-sized vessels temporarily and this includes the coronary arteries this response can damage collagen and damage elastic fibers in the vessel walls and can lead to loss of their normal structural integrity despite the repair that occurs the disrupted structural integrity results in ballooning or aneurysm formation the clinical features of Kawasaki is usually a child less than five years old with high fevers for more than five days and irritability some classic findings in Kawasaki can be remembered with the abbreviation cream c is for conjunctivitis bilateral non pearl and r is for rash polymorphous or maculopapular rash e is for erythema and/or edema of the hands or feet a is for adenopathy lymphadenopathy specific minister vehicle chains and M is for mucous membrane changes which include red tongue strawberry tongue and dry cracked lips the diagnosis of Kawasaki is made if the child has four of the five following letters in cream as well as having a fever for more than five days for children who present with a purpura or a petechial rash with fever the differential is broad a good start is to divide differentials into thrombocytopenia and non thrombocytopenia induced rash but some important differential diagnosis the to remember include measles where there is evidence of exudative conjunctivitis complex spots and rash which tend to occur in the head and migrate to the trunk drug reaction is important differential which leads to a generalized rash eruption all over the body usually itchy and another important feature is the Angela demon which is swelling infections is a fundamental differential and includes streptococcus infections and remember infections are associated with the development of Kawasaki so for example streptococcus pharyngitis and streptococcal pharyngitis can then also lead to scarlet fever streptococcus pharyngitis can also lead to rheumatic fever an autoimmune response to destructor Cox infection another differential are the Staphylococcus infections which typically include the skin and is also associated with the development of Kawasaki disease Staphylococcus infections differentials include Staphylococcus called– skin syndrome which is characterized by red blistering skin that looks like a burn another is toxic shock syndrome which is caused by the release of bacterial toxins from the Staphylococcus species and is associated with tampon use another important differentials and also potentially the trigger for Kawasaki or viral infections which can also manifest as a maculopapular rash finally a very life-threatening differential is Steven Johnson syndrome investigations to order include a full blood count to look for signs of infection EU C's for kidney involvement lfts to look for viral causes affecting the liver CRP and ESR which are inflammatory markers these should be high in Kawasaki as well as in infections urinalysis is good to look for evidence of Whites you know increase in white cell count finally it is suggested that an echocardiogram should be performed once the diagnosis of Kawasaki disease is made as well as 6 to 10 weeks after to check for myocardial information and coronary artery aneurysm formation remember the main complication of Kawasaki disease is coronary artery aneurysms but it is not uncommon for aneurysms to occur anywhere along the branches of the aorta once diagnosis of Kawasaki is made it is essential that a pediatrician is involved admit the child and commence immunoglobulin intravenously as well as aspirin commencing intravenous immunoglobulin within 10 days of fever onset has shown to reduce cardiac complications the complications of Kawasaki are mainly cardiovascular and include coronary artery aneurysms as well as artery aneurysms anywhere else myocardial infarction pericarditis and Myositis thank you for watching that concludes the video on medium sized vessel vasculitis you

17 thoughts on “Polyarteritis Nodosa and Kawasaki Disease (Medium Vessel Vasculitis) – Symptoms, pathophysiology”

  1. Sir can you put a picture of the whole slide at the end of video so that we can take pictures and read it again

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