HNG 2024 Flashcards
Pyoderma gangrenosum category
an ulcerative disorder that falls into the category of neutrophilic dermatoses
The most common associated systemic disorders of pyoderma gangrenosum?
rheumatoid arthritis, inflammatory bowel disease, and other autoimmune and inflammatory conditions. Both solid tumors and hematologic malignancies. Pyoderma gangrenosum is associated with ulcerative colitis in 5% to 12% of cases and is associated with Crohn disease in 1% to 2% of cases.
pathogenesis of pyoderma gangrenosum
not fully understood. It is thought to involve genetic mutations, neutrophil dysfunction, and immune/inflammatory dysregulation. Some lesions of pyoderma gangrenosum have been found to have a proliferation of clonal T-cells. In addition, inflammasomes have been postulated to be involved in the neutrophil chemotaxis that occurs in these lesions. Inflammasomes are complexes of receptors that are part of innate immune system signaling. Some cases of pyoderma gangrenosum are associated with a mutation in Janus kinase 2, which is involved in the production of several cytokines. Abnormal cytokine signaling by T cells and macrophages is likely a component of the disease process. Lesions of pyoderma gangrenosum have been found to have increased levels of inflammatory mediators. For example, IL-23 has been found to be increased in lesions of pyoderma gangrenosum. IL-23 is important in activating neutrophils and stimulating IL-17 mediated inflammation
Inflammasomes
Inflammasomes are complexes of receptors that are part of innate immune system signaling.
Histopathology of pyoderma gangrenosum
The disease is a clinical and histologic diagnosis of exclusion as the histologic features are non-specific. The goal of the biopsy is to exclude other causes of ulceration. Early lesions of pyoderma gangrenosum should show an infiltrate of neutrophils in the dermis. Lesions may demonstrate necrotic dermal vessels. Direct immunofluorescence of biopsy specimens of pyoderma gangrenosum is nonspecific.
Sweet syndrome
Sweet syndrome, also called acute febrile neutrophilic dermatosis, is a rare disorder that typically presents with acute-onset tender plaques or nodules, fever, arthralgia, ophthalmologic manifestations, headaches, and rarely, oral or genital lesions.
Pathergy
an exaggerated response to a minor skin injury or worsening of an existing wound with minimal insult or trauma. This has a wide array of implications for the patient including debridement and simple wound care. This also makes the decision to perform certain surgeries and procedures much more difficult. Lastly, insults to the skin that would be nearly meaningless for most people can be devastating for some patients with pyoderma gangrenosum.
Major Criteria of pyoderma gangrenosum
- Rapid progression of a painful, necrolytic cutaneous ulcer with an irregular, violaceous, and undermined border.
- Other causes of cutaneous ulceration have been excluded
Minor Criteria of pyoderma gangrenosum
- History suggestive of pathergy or cribriform scarring
- Systemic diseases associated with pyoderma gangrenosum
- Histopathologic findings (sterile dermal neutrophilia, +/- mixed inflammation, +/- lymphocytic vasculitis)
- Treatment response (rapid response to systemic steroid treatment)
differential diagnosis of pyoderma gangrenosum
infectious diseases like mycobacterial infection and deep fungal infections. Also included in the differential are noninfectious diseases such as iododerma or bromoderma. Other causes of ulcers to consider are arterial ulcers and Martorell ulcers. Arterial ulcers may have associated weakened pulses on the corresponding anatomical side.
What are the risk factors for oral cancer?
Alcohol, smoking, betel nut, immunosuppression, HPV
What are the common sites of oropharyngeal carcinoma?
Underside of tongue and floor of the mouth
What are the 3 layers of a tooth?
Enamel, Dentin, Root
What is the job of the mouth?
Mastication, taste perception, initial starch digestion, swallowing, speech, facial expression.
What role does saliva play in the mouth?
Moistens food, buffers oral contents, protects teeth & mucosa, supplies Ca++ and PO4, neutralize
acid.
calcium phosphate
calcium salt of phosphoric acid with a chemical formula Ca3(PO4)2. It is also known as Calcium phosphate tribasic or Tricalcium Phosphate. Calcium phosphate stones account for approximately 15% of kidney stone disease. Calcium phosphate stones tend to grow in alkaline urine, especially when Proteus bacteria are present.
betel quid
The most common method of using betel nut is to slice it into thin strips and roll it in a betel leaf with slaked lime (powder) or crushed seashells. This leaf package is known as a betel quid, betel nut chew, betel chew, betel pan or betel paan (India)
What is CREST syndrome?
calcinosis cutis, Raynaud’s phenomenon, Esophageal dysmotility, sclerodactyly and telangiectasia,
En coup de sabre
a rare subset of linear morphea. It usually presents as a pan-sclerotic plaque over the frontoparietal scalp with surrounding scarring alopecia. The patients may have central nervous system involvement in addition to the cutaneous findings
Eosinophilic esophagitis histological criteria
Major criteria: ≥ 15 eosinophils per high power field (40x magnification) (Arch Pediatr 2019;26:182)
Minor criteria: extreme basal zone hyperplasia with papillary hyperplasia, eosinophils concentrated in the surface epithelium as opposed to the base, eosinophilic microabscesses, eosinophil degranulation, surface desquamation, lamina propria fibrosis
Eosinophilic esophagitis gross description
Major criteria (Gut 2013;62:489)
Mucosa edema
Exudate or white plaques
Longitudinal furrows
Circular esophageal rings (pseudotrachea)
Esophageal stenosis
Minor criteria (Gut 2013;62:489)
Feline esophagus
Concentric mucosal rings observed with some types of motility that disappear with air insufflation
Narrow caliber esophagus
Crêpe paper esophagus
Mucosal laceration or fragility with passage of instruments before dilation
Helicobacter heilmannii
Very rare compared to H. pylori
More common in children; due to contact with farm animals or household pets
Helical, 3.5 - 7.5 microns, 0.9 microns in diameter
Long tight spirals; thicker and twice as long as H. pylori and usually visible with H&E stain
Autoimmune Hepatitis
ANA, SMA, LKM and/or SLA antibodies
F:M = 7:3
Associated extrahepatic autoimmune disorder: Thyroiditis, Sjogren syndrome, Rheumatoid arthritis.
Hypergammaglobulinemia
Responsive to corticosteroids.
Histo: often sever inflammation and necrosis with abundant plasma cells.
Explain stomach acid control
Two most common causes of peptic ulcer disease
H pylori
NSAIDs
two known types of autoimmune hepatitis
Type 1 is distinguished by the presence of anti-smooth muscle antibodies (ASMA) with or without anti-nuclear antibodies (ANA). Type 2 autoimmune hepatitis presents with positive anti-liver/anti-kidney microsome (anti-LMK) type 1 antibodies or anti-liver cytosol (anti-LC) type 1 antibodies.
Auerbach plexus
Myenteric plexus, between the inner circular and outer longitudinal smooth muscle layers of the muscularis propria.
plexus between the inner circular and outer longitudinal smooth muscle layers of the muscularis propria.
Auerbach plexus. Myenteric plexus.
Dieulafoy lesion
an enlarged (1 to 3 mm) submucosal blood vessel that bleeds in the absence of any abnormality such as ulcers or erosions. The majority of the lesions arise in the stomach at the lesser curvature, within 6 cm of the gastroesophageal junction, as this region receives its arterial blood supply directly from the branches of the left gastric artery
Histopathology of Dieulafoy lesion
A biopsy is not recommended for the diagnosis of Dieulafoy lesions due to an increased risk of bleeding. Dieulafoy lesion can be distinguished from gastric ulcers on histology by a lack of subintimal fibrosis and mucosal inflammation.
Angiodysplasia vs Dieulafoy lesion
Angiodysplasia can be differentiated from Dieulafoy lesions by angiography that reveals the presence of arteriovenous shunting and vascular ectasia; by histological examination of the lesion, which reveals the presence of abnormal submucosal vessels.
Dieulafoy lesion
a normal blood vessel with an abnormally wide diameter of 1 to 3 mm, protruding into the mucosa from the submucosa. The protrusion results in a small wall defect in the gastrointestinal tract with fibrinoid necrosis at the base of the lesion; 70% of these lesions are found in the stomach, usually along the lesser curvature.
Pipestem fibrosis liver ultrasound, liver schistosomiasis
kayexalate / sodium polystyrene sulfonate
kayexalate / sodium polystyrene sulfonate
Bile acid sequestrant
Sevelamer / Renvela / Renagel
Pill fillers seen in pill esophagitis.
