Medical Infographics

Sister Mary Joseph’s Nodule

Defined as neoplastic lesion in the periumbilical region arising as a primary tumor or representing as a site of metastasis from visceral organ malignancies such as from the gastrointestinal tract and the reproductive organs. The overall incidence is 1-3% in general population with malignancies. The primary site of malignancy associated is significantly different in men and women. The most common primary site in men is the stomach followed by the colon and pancreas, whereas in women, the most common site is the ovary followed by endometrium, colorectal, and pancreas.

The prognosis of patients presenting with Sister Mary Joseph’s nodule is generally poor as it is a sign of advanced malignancy. Management of the disease should consider patient preference, the clinical state of the patient, and the etiology of the primary malignancy.

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Porcelain gallbladder (PGB)

Term porcelain gallbladder (PGB) is often used to describe calcification of the gallbladder wall. When infiltrated by extensive calcium deposits, the gallbladder wall can become fragile, brittle and bluish in appearance, resulting in a ‘porcelain’ appearance.

The true incidence of porcelain gallbladder is unknown, but it is reported to be 0.6-0.8%, with a male-to-female ratio of 1:5. Most porcelain gallbladders (90-95%) are associated with gallstone. Mean age at diagnosis is 32 to 70 years.

Patients with porcelain gallbladder are usually asymptomatic, and the condition is usually found incidentally on plain abdominal radiographs, sonograms, or CT images.

Based on early studies which revealed a high association between porcelain gallbladder and gallbladder adenocarcinoma (22-30% of porcelain gallbladders developing gallbladder adenocarcinoma), cholecystectomy has been routinely performed when a porcelain gallbladder is identified.

More recent studies have cast some doubt on the association, and the risk of gallbladder cancer associated with calcification of the wall may be as low as 5-7%. There is no accepted follow-up interval, but the annual incidence of developing gallbladder cancer is likely to be <1% per year.

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Dupuytren’s contracture

Dupuytren’s contracture is predominantly a myo-fibroblastic disease that affects the palmar and digital fascia of the hand and results in contracture deformities. The most commonly affected digits are the fourth and fifth digits. It is a genetic disorder that often is inherited in an autosomal dominant fashion, but is most frequently seen with a multifactorial etiology. There are a number of factors that are believed to contribute to the development or worsening of this disease.

These include:

Men are more likely to develop the condition than women.
People of northern European (English, Irish, Scottish, French, and Dutch) and Scandinavian (Swedish, Norwegian, and Finnish) ancestry are more likely to develop the condition.
Dupuytren's often runs in families.
Drinking alcohol may be associated with Dupuytren's.
Diabetes, HIV, Vascular disease, smoking and seizure disorders are more likely to have Dupuytren's.
Incidence of the condition increases with age.

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Dual-energy x-ray absorptiometry (DEXA)

Uses x-rays at two energy levels to determine the bone mineral content.
Major role in diagnosis of osteoporosis, the assessment of patients' risk of fracture, and monitoring response to treatment.
T-score is a number of standard deviations between the patient’s mean BMD and the mean of the population compared with reference populations matched in gender and race.
Z-score is the number of standard deviations above or below the mean of age-matched controls.
DEXA could be used to measure bone density at many skeletal sites, two sites are typically measured: the first four vertebrae of the lumbar spine posteroanterior, and the proximal femur (“hip”), including the femoral neck and the trochanteric areas and total hip measurement. Femoral neck and lumbar spine are the gold standard for evaluating osteoporosis, with good accuracy and high precision.
All women 65 years and older and men 70 years and older should be screened for asymptomatic osteoporosis.

The World Health Organization (WHO) defines T-scores as:

Greater than or equal to -1.0: normal
Less than -1.0 to greater than -2.5: osteopenia
Less than or equal to -2.5: osteoporosis
Less than or equal to -2.5 plus fragility fracture: severe osteoporosis

Clinical risk factors included in WHO fracture algorithm

Age
Low body mass index
Prior fracture after age 50
Parental history of hip fracture
Current smoking habit
Current or past use of systemic corticosteroids
Alcohol intake >2 units daily
Rheumatoid arthritis

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Splenectomy

Patients who undergo splenectomy are at increased risk of infections secondary to encapsulated organisms: H Influenzae, Streptococcus pneumoniae & Neisseria meningitidis.
Vaccinations against these organisms are highly recommended in patients who have undergone splenectomy.
Careful attention must be paid to post-splenectomy patients presenting with febrile illnesses as they may require more aggressive, empiric antibiotic therapy.
Palpation of spleen ---see below

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Niacin Deficiency

Niacin Deficiency (Pellagra)

A distinctive dark red rash may appear on the hands, feet, calves, neck, and face. The tongue and oral mucosa can also become dark red.

Niacin deficiency frequently coexists with deficiencies in protein, riboflavin (vitamin B2), and vitamin B6.

Pellagra develops when the diet is deficient in both niacin and tryptophan, an amino acid that the body can convert into niacin.

The condition primarily affects the skin, gastrointestinal tract, and central nervous system.

Pellagra may also develop in the context of:

Hartnup disease, in which tryptophan absorption is impaired
Carcinoid syndrome, where tryptophan is diverted toward serotonin synthesis rather than niacin production
Chronic alcoholism and isoniazid therapy, both of which can interfere with niacin metabolism or availability

Diagnosis is typically based on dietary history and clinical features. Laboratory confirmation may include measuring niacin metabolites in the urine, although this test is not routinely available. A therapeutic trial of niacin that results in symptom resolution can also support the diagnosis.

Treatment:
The preferred treatment is nicotinamide, a form of niacin that does not cause the flushing, itching, burning, or tingling commonly associated with nicotinic acid.

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White Blood Cell Scan

Indium 111- tagged white blood cell scan is a type of imaging modality used to help identify regions of inflammation and thus infections when other imaging studies are equivocal or contraindicated.

The test is used for diagnostic purposes in the evaluation of prosthetic joint infections, osteomyelitis, vascular graft infections, intra-abdominal infections, abscesses, endocarditis, foot ulcers, infected implanted devices such as central venous catheters, fevers of unknown origin when there is a high probability of infection, and Inflammatory bowel disease.

Sensitivity 60 to 100% and specificity 69 to 92%.

White blood cells are obtained from a blood sample from a patient, are tagged with the radioisotope indium-111, and then re-injected intravenously into the patient. These labeled leukocytes localize to a region of inflammation visible on the whole body or regional nuclear imaging with bone scintigraphy.

Recommended dose for adults is 0.3 to 0.5 mCi

Prior IV antibiotics may produce false negative result.

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Pneumobilia vs Portal venous gas

Pneumobilia

Also known as aerobilia. Accumulation of gas in the biliary tree. Seen as linear branching gas within liver most prominent in central large caliber ducts as the flow of bile pushes gas toward the hilum. Gas within the biliary tree tends to be more central, whereas gas within the portal venous system tends to be peripheral (carried along by the blood). Also, biliary gas is anti-dependent, and typically fills the left lobe of the liver.

“Saber sign”: Supine radiographs often demonstrate a sword-shaped lucency in the right paraspinal region representing gas from the common duct and the left hepatic duct. Present in ~50% of patients with pneumobilia.