Author
Lars Grimm, MD, MHS
House Staff
Department of Internal Medicine
Duke University Medical Center
Durham, North Carolina
Disclosure: Lars Grimm, MD, MHS, has disclosed no relevant financial relationships.
Editor
Jose Varghese, MD
Associate Professor of Radiology
Boston University School of Medicine
Boston, Massachusetts
Disclosure: Jose Varghese, MD, has disclosed no relevant financial relationships.
Plain abdominal radiographs are commonly ordered in inpatient and outpatient settings for patients with a variety of abdominal complaints. In addition to the gastrointestinal system, a variety of critical and/or incidental findings in the genitourinary, hepatic, biliary, and vascular systems can all be identified on abdominal radiographs. The plain abdominal radiograph shown demonstrates milk-of-calcium bile with a stone (arrow) from precipitated calcium carbonate within the gallbladder lumen.
The patient is suffering from emphysematous cholecystitis caused by an infection of the gallbladder by a gas-forming organism. The classic radiographic findings are a curvilinear outline of the gallbladder wall caused by air in the right upper quadrant. It may be either calculous or acalculous, as in this case. Changes may be visible earlier in the disease course on ultrasound or computed tomography (CT).
The radiographs reveal calcifications within the wall of the abdominal aorta outlining an abdominal aortic aneurysm. An outpouching is seen on the frontal radiograph to the left of the spine (curved line), but the right margin overlies the spine, making it difficult to discern if it is ectasia or an aneurysm. A lateral radiograph in the same patient reveals the full extent of the aneurysm and confirms the diagnosis (circle). Aortic aneurysms are usually an incidental finding on plain radiographs and can best be evaluated with CT, ultrasound, or magnetic resonance imaging.
The radiograph reveals coarse calcifications in the anatomic location of the pancreas, consistent with the diagnosis of chronic calcifying pancreatitis. Precipitation of proteinaceous material in the pancreatic ducts form plugs that calcify and build up. Long-standing alcohol abuse is invariably the most common cause, found in more than 70% of cases.
A recent immigrant from Argentina presents to his primary care provider for an initial visit. He has worked as a farmer his whole life and lived in a rural area. His primary complaints are a vague abdominal pain and a feeling of abdominal distention. A plain abdominal radiograph is ordered and reveals what critical finding?
The radiograph reveals multiple large curvilinear calcifications overlying the liver. The list of differential considerations would include cyst, abscess, or metastatic disease, but in this patient from a rural area of South America the most likely diagnosis is hydatid cysts. Hydatid cysts are caused by the larval cystic stage of a tapeworm from the genus Echinococcus, endemic to the Mediterranean, South America, Africa, and Australia. The classic radiographic features are large well-defined curvilinear or ring-line calcifications in the right lobe of the liver. In most patients they are asymptomatic until they either rupture or cause mass effect.
The radiograph reveals a pyriform opaque mass with curvilinear calcification in the right upper quadrant from a porcelain gallbladder. The gallbladder wall may be diffusely calcified or have irregular stippled calcifications. This is usually an incidental finding in asymptomatic patients. Although it was originally thought that there was a high association between porcelain gallbladder and adenocarcinoma, more recent research has revealed a much weaker association and in patients with diffuse calcification there is no increased risk for cancer.
A patient presents to his primary care physician with complaints of intermittent abdominal pain, nausea, and vomiting for the previous few days. He was finally able to get an appointment but by now his symptoms have resolved. His physician orders a plain radiograph of the abdomen, which reveals what likely finding to explain his previous symptoms? Image courtesy of Wikimedia Commons.
The radiograph reveals multiple calcifications (circles) overlying the kidneys from nephrolithiasis. The patient's symptoms were thus likely renal colic from spontaneous passage of a stone. Knowledge of the anatomic location of the kidney is important to differentiate renal stones from other common, benign sources of a calcification seen on radiographs, such as phleboliths (arrows). Approximately 90% of renal calculi can be detected with radiography, but uric acid stones may be missed. Image courtesy of Wikimedia Commons.
Stones may also be detected anywhere along the length of the ureter especially at the ureterovesicular junction (arrow) where the ureter enters the bladder. This is a common location for stones to become stuck and it may be difficult to differentiate them from phleboliths. Phleboliths are benign venous calcifications commonly found in the pelvis.
The radiograph reveals multiple calculi distributed in a pyriform shape in the right upper quadrant, diagnostic of gallstones. Only 15% of gallstones will appear on plain radiographs, compared with 85% on CT. It is important to recognize that cholelithiasis in isolation does not mean cholecystitis and must be placed in the appropriate clinical circumstances. The second critical finding on this radiograph is pneumperitoneum in the left upper quadrant (arrow) which could easily be missed if one is distracted by the gallstones. This patient underwent a laparotomy and was found to have a perforated cecal carcinoma.
The radiograph reveals bilateral renal calculi with a staghorn calculi on the right. Any stone that occupies 2 or more renal calyces is termed a staghorn calculi, but 75% of cases are struvite stones composed of a struvite-carbonate-apatite matrix. These typically develop from urease-producing bacteria, most commonly Ureaplasma urealyticum and Proteus species. These stones will not pass spontaneously and if they grow too large, they need to be surgically removed.
The radiograph reveals hepatomegaly and multiple calcifications in the upper abdomen (arrows) concerning for hepatic metastases. The patient was ultimately found to have medullary carcinoma of the thyroid with extensive metastatic spread. The liver is a very common location for metastatic spread from a variety of malignancies. Mucin-secreting colorectal cancer is the classic malignancy to produce metastatic liver calcifications. Other nonmalignant processes may produce liver calcifications, but they usually tend to be more solid and less amorphous.
Author
Lars Grimm, MD, MHS
House Staff
Department of Internal Medicine
Duke University Medical Center
Durham, North Carolina
Disclosure: Lars Grimm, MD, MHS, has disclosed no relevant financial relationships.
Editor
Jose Varghese, MD
Associate Professor of Radiology
Boston University School of Medicine
Boston, Massachusetts
Disclosure: Jose Varghese, MD, has disclosed no relevant financial relationships.
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