Abdominal Pain With Stripes
Most of us at some point during our training have been advised of the saying, "When you hear hoofbeats, think of horses, not zebras." While in the majority of cases it is true that things usually are as they appear, this case study reminds us to remember to keep alert for "zebras" that may enter your practice in the form of an unusual presentation of a common illness.

A. B. was the first patient scheduled for the day. As she came down the hall, it was clear that the chief complaint of abdominal pain was accurate. A. B. was ambulating independently, but holding her lower abdomen and shuffling her feet. She slowly walked into the room with her mother at her side.

A. B. was a twelve-year-old Black female, although physically she appeared much older. She was the only child of a single mother. She had been a patient in our practice from birth until two years of age, at which point a change in insurance caused her to switch to another provider until the age of eleven. Since returning to our practice she had been seen twice in our office, once for tinea corporis and once for an upper respiratory infection with otitis media. No previous medical records were available. Her past medical history was unremarkable. She had been feeling well until 10 p.m. the night before, when she was bothered by mild abdominal pain. She had two formed stools at midnight and 1 a.m., and vomited once at 3 a.m. Having snacked on pizza the evening before, her mother attributed the discomfort to gas and tried to relieve her discomfort with Tylenol and Alka Seltzer. There was no fever, but by the early morning hours the pain was worsening, prompting the mother to call for an appointment.

On the exam table, the patient was clearly guarding her abdomen but did not appear to be in acute distress. She was able to answer questions and move about the exam room, although she was most comfortable lying down. A. B. denied being sexually active. Her last menstrual period was approximately four weeks ago. Her vital signs were normal: temperature 97.3°F, blood pressure 124/80, heart rate 80. Her physical examination was normal, except for tenderness of the left upper quadrant and both lower quadrants, and generalized rebound tenderness. There was no abdominal distention, and no masses were appreciated.

A complete blood count (CBC) was drawn by fingerstick but was unreadable due to what appeared to be very opaque serum. She was unable to give a urine specimen as she had urinated just prior to arriving for her appointment. A pediatrician was consulted to examine the patient, and it was agreed that further lab work and a surgical consult for an acute abdomen needed to be obtained in the emergency room.

While the patient's mother prepared to take her daughter to the hospital, she was observed in the office. Her vital signs remained stable, although she vomited twice prior to being taken to the hospital.

After lunch, a disturbing phone call was received from the emergency room physician. After arriving at the hospital, the patient was sent to the toilet to obtain a urine sample. She became unresponsive and pulseless in the hallway. She required intubation, defibrillation, Dopamine, and Lidocaine. She was transferred to the medical intensive care unit. Before being transferred to a tertiary care hospital in a neighboring city, a CT scan of the abdomen was obtained, showing large amounts of fluid in the abdomen with an abnormal appearing spleen. Surgical exploration that afternoon revealed an impressive fulminate pancreatitis, with large amounts of fluid in the abdomen. The abdomen was flushed and closed, but the patient postoperatively had a Glasgow Coma Scale score of three. She was placed on high dose epinephrine, but she displayed poor cardiac output, no urine production, and her pupils were fixed and dilated. She was not expected to survive and did indeed die the following day.

What should be in your differential diagnosis for a patient with acute abdominal pain? The differential diagnosis for acute abdominal pain is extensive, ranging from benign gasteroenteritis to a potentially lethal ailment. Common causes include appendicitis, mesenteric adenitis, gasteroenteritis, pha-ryngitis, pneumonia, pyelonephritis, dietary indiscretion, and food poisoning. Other less common causes in the general pediatric population include pelvic inflammatory disease, hepatitis, infectious mononucleosis, peritonitis, obstruction, cholecystitis, acute glo-merulonephritis, leukemia, pancreatitis, hernia, abdominal abscess, hemolytic crisis, or tumor (Tunnessen, 1999). Ectopic pregnancy should also be considered. This patient presented with an acute onset of worsening abdominal pain, which was diffuse but more prominent in the left upper quadrant. She did display rebound tenderness on exam. She had no fever, intermittent vomiting without diarrhea, and no rash. A CBC was initially unreadable in the office due to the lipemic appearance of the serum. Given these findings, additional laboratory studies along with radiologic and surgical consults were necessary to determine the cause of the abdominal pain. What could be the significance of the opacity of the serum for this patient? The opaque appearance of the serum was due to lipemia. Although the blood sample obtained in the office appeared cloudy and was unreadable by the machine used to perform complete blood counts, the more sophisticated machine in the hospital identified the specimen as lipemic. It is not clear why serum triglycerides may become elevated as a result of acute pancreatitis, but extremely high levels of triglycerides can be both a cause and a result of pancreatitis. This patient had no known family history of elevated cholesterol or triglycerides, although levels were not available at the time of illness. What was atypical in the way this case of pancreatitis presented, and what would one expect to see in a more common presentation on this illness? The presentation of this patient was not typical. The transition from initial symptoms to necrosis and death was extremely fast, progressing from mildly ill to unresponsive within fourteen hours. The patient remained afebrile during this time and vomited only three times before becoming unresponsive in the emergency room. Pancreatits is an inflammation of the pancreas, and can be an acute or chronic disorder. In adults it is often associated with excessive alcohol consumption or gallstones. The most common causes in children include blunt abdominal trauma and viral infections (Oski, 1994). Other causes include blockage of the pancreatic duct, elevated calcium levels, drug side effects (including use of valproate) (Brown, 2003), or high triglycerides (Vogin, 2002). In children, the cause is often idiopathic. The disease process occurs when the pancreatic proenzymes are activated, which leads to the release of active proteases, which cause the pancreas to autodigest, releasing more proteases. Edema appears early, and can be followed by necrosis, disruption of blood vessels, hemorrhage, and peritoneal inflammation (Oski, 1994). An uncomplicated case of acute pancreatitis has an excellent prognosis. Most cases are of unknown etiology. The patient usually presents with abdominal pain that is epigastric and steady. Symptoms usually have a mild onset and worsen over two to four days. Persistent vomiting and fever are usually present. The patient appears acutely ill and often favors a position with knees and hips flexed to decrease discomfort. The abdomen may be distended, and the pain increases slowly over 24-48 hours. In a recent study of adult patients with pancreatitis who required surgery, the mean period from the onset of disease to necrosectomy was fifteen days (Gotzinger et al., 2003). An elevated serum amylase may help with the diagnosis, although other causes of elevated serum amylase include parotitis, pancreatic pseudocyst, ascites, abscess, eating disorders, appendicitis, intestinal obstruction, peptic ulcer perforation, burns, renal insufficiency, or metabolic acidosis (ie, diabetic shock). The acute hemorrhagic form of pancreatitis, as seen in this patient, is a severe form of the disorder and is rare in children. The patient usually appears acutely ill with severe vomiting and abdominal pain. Physical examination may reveal the Cullen sign (bluish area around the umbilicus) or the Grey Turner sign (bluish area around the flanks). The pancreas becomes necrotic, which can lead to a hemorrhagic mass. Mortality rate for this form of pancreatitis can be close to 50% due to shock, renal failure, disseminatd intravascular coagulation (DIC), massive GI bleed, or infection.

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  Brown, 2003. Brown University Child and Adolescent Psychopharmacology Update 2003;5:5-7.
  
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  Gotzinger et al. 2003 Gotzinger P, Wamser P, Exner R, Schwarnzer E, Jakesz R, Fugger R. Surgical treatment of severe acute pancreatits: Timing of operation is crucial for survival. Surgical Infections 2003;4:205-211.
  
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  Oski, 1994. Oski F. In Principals and practice of pediatrics, eds Philadelphia: J.B. Lippincott Co.; 1994. 1908-1910.
  
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  Tunnessen, 1999. Tunnessen, W. (1999). Signs and symptoms in pediatrics. St. Louis: J.B. Lippincott Co. Vogin, G. Understanding pancreatitis. Available at http://www.aolsvc.health.webmd.aol.com.Retrieved 2002.
  
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  Vogin, 2002. Vogin, G. "Understanding pancreatitis." Retreived October 4, 2004, from http://aolsvc.health.webmd.aol.com/content/article/10/1680_54742.htm.