Medical Infographics

Diabetes and hemoglobin A1c

In patients ≥65 years of age treated with medication for type 2 diabetes, hemoglobin A1c values of 7%–8% have shown the greatest reduction in mortality in multiple studies. The specific hemoglobin A1c target between 7% and 8% should be based on shared decision-making and the overall condition of the patient at that specific age, with goals in the lower 7% range for those with good to excellent functional status. It is suggested that lower hemoglobin A1c values are associated with frequent hypoglycemia, which presents a greater risk than a higher hemoglobin A1c value alone. Hemoglobin A1c values over 9% are associated with greater mortality. Thus, while the risk of complications increases linearly with hemoglobin A1c, mortality has a U-shaped curve. Management of blood pressure and treatment with statins improves mortality in these patients as well and is important in addressing overall cardiovascular risk.

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Xanthogranulomatous pyelonephritis

Xanthogranulomatous pyelonephritis is an uncommon, severe, subacute, or chronic suppurative process characterized by destruction and replacement of the renal parenchyma by granulomatous tissue containing histocytes and foamy cells. It is most often associated with chronic obstruction and stones with ongoing infection. It is also referred to as a pseudotumor due to an enlarged kidney resembling a tumor and the ability of local invasion and destruction.

The etiology remains unknown. However, most of the cases result from chronic urinary obstruction and infection. The organisms most commonly associated with XGP are Escherichia coli, Proteus mirabilis, Pseudomonas, Enterococcus faecalis, and Klebsiella, etc. Urinary obstruction occurs as a result of calculus, most commonly, staghorn calculus (in almost 80% of patients), which serves as a nidus for infection resulting in the destruction of the renal parenchyma.

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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: