What is in the Differential Diagnosis of an Abdominal Mass?

Patient Presentation
A 3-year-old male came to clinic because his parents noted that his abdomen was hard on the right side when they squeezed his abdomen while they were playing 2 days ago.
The past medical history was normal.
The family history was negative.
The review of systems was negative including weight loss, chills, fever, sweats, bone or other pain, adenopathy, bleeding, bruising or change in bowel or bladder habits. He also had normal satiety and was eating well.
The pertinent physical exam with normal vital signs, growth and development. Abdomen reveals a diffuse solid mass in the right mid- to upper quadrant. No splenomegaly was noted. Shoddy anterior cervical and inguinal nodes were noted. Skin examination was normal.
The work-up showed normal complete blood count, erythrocyte sedimentation rate, lactate dehydrogenase, liver enzymes, and total bilirubin.
The radiologic evaluation revealed a large mass that appeared adherent to the liver that did not appear to be arising from the kidney or the adrenal grand. The patient then had an alpha-fetoprotein level drawn that was significantly elevated and a surgical biopsy confirmed a
diagnosis of hepatoblastoma. The child is undergoing chemotherapy to shrink the tumor and surgical resection is planned for the future.


Figure 33 – Axial image from a CT scan of the abdomen performed with intravenous and oral contrast. A large, inhomogenous mass is seen on the right side of the abdomen, compressing the right kidney posteriorly. The mass did not appear to arise from the right adrenal gland or right kidney.

Discussion
Approximately 70% of liver tumors are malignant with hepatoblastoma predominating in those < 3 years and hepatocellular carcinoma becoming more common in older children.
Hepatoendothelioma is the most common benign tumor. Liver tumors usually present as a painless abdominal mass but they can also cause weight loss, anorexia, fever or jaundice.
Alpha-fetoprotein levels are elevated in hepatoblastoma and hepatocellular carcinoma. Hepatoblastoma is more common in children with Beckwith-Wiedemann syndrome and hemihypertrophy.
Resection is the mainstay of treatment but chemotherapy to shrink a large tumor or after resection is also used. Favorable factors for prognosis are decreasing alpha-fetoprotein levels and complete resections.
Overall disease free survival is 70% except for those patients presenting with initial metastatic disease.

Learning Point
The differential diagnosis of an abdominal mass depends on the location, age of the patient, and imaging results but includes:

  • Abdominal organs that are normal but are mistaken as a mass – e.g. liver, spleen, kidney, aorta, bladder, uterus, etc.
  • Organ enlargement – e.g. storage disease, congestive heart failure, infection, etc.
  • Gastrointestinal anatomic abnormality – e.g. bowel duplication, stenosis, appendiceal abscess, etc.
  • Renal abnormalitiy – e.g. hydronephrosis, megaureter, polycystic kidney disease, renal vein thrombosis, etc.
  • Tumors – primary or metastatic, but most commonly neuroblastoma, Wilm’s tumor, and lymphoma. Other malignancies include hepatocellular carcinoma, hepatoblastoma, rhabdomyosarcoma,
    ovarian or testicular germ cell tumors, and primary neuroectodermal tumors. Benign tumors may also occur such as teratomas.

  • Cysts – e.g. choledochal cyst, mesenteric cyst, pancreatic pseudocyst, omental cyst, ovarian cyst, meconium pseudocyst, urachal cyst, etc.
  • Miscellaneous – e.g. abscess, fecal mass, hydrops of gall bladder, intussusception, pregnancy, pyloric stenosis, hydrometrocolpos, adrenal hemorrhaage, etc.

Questions for Further Discussion
1. What should be included in the workup of an abdominal mass? Why?

Related Cases

To Learn More
To view pediatric review articles on this topic from the past year check PubMed.

Information prescriptions for patients can be found at MEDLINEplus for this topic: Liver Cancer

To view current news articles on this topic check Google News.

Sheldon SH Levy HB. Pediatric Differential Diagnosis. Second Edition. Raven Press: New York. 1985:1-4.

Woodhead JC. Pediatric Clerkship Guide. Mosby. St. Louis MO, 2003:115-120.

Rudolph CD, et.al. Rudolph’s Pediatrics. 21st edit. McGraw-Hill, New York, NY. 2003:1375-1376, 1620-21.

ACGME Competencies Highlighted by Case

  • Patient Care
    2. Essential and accurate information about the patients is gathered.
    3. Informed decisions about diagnostic and therapeutic interventions based on patient information and preferences, up-to-date scientific evidence, and clinical judgment is made.
    4. Patient management plans are developed and carried out.
    7. All medical and invasive procedures considered essential for the area of practice are competency performed.
    9. Patient-focused care is provided by working with health care professionals, including those from other disciplines.

  • Medical Knowledge
    10. An investigatory and analytic thinking approach to the clinical situation is demonstrated.
    11. Basic and clinically supportive sciences appropriate to their discipline are known and applied.

    Author
    Donna M. D’Alessandro, MD
    Associate Professor of Pediatrics, Children’s Hospital of Iowa

    Date
    January 30, 2006

  • When Do Cyanotic Congenital Heart Diseases Present?

    Patient Presentation
    An 6 week old male came to his local pediatrician’s office with 2 days of nasal congestion that was clear. He was formula feeding without problems and had started daycare several days ago. He had no fevers.
    The past medical and social history revealed that he was a previously well, full-term baby.
    The family history was negative.
    The pertinent physical exam revealed a vigorous male with weight, length and head circumference in the 25-75% and growing appropriately. His heart rate = 135, respiratory rate = 30 and normal blood pressure. He was afebrile.
    He was noted to have purplish lips, hands and feet. He had clear nasal discharge.
    On heart examination, he had a grade III/VI systolic murmur loudest at the lower left sternal border that was described as high frequency. It was not holosystolic but occured through most of systole.
    There was a normal S1, S2 with a normal split of S2. There was no other murmurs or thrills.
    The liver was 1.5 cm below the right costal margin and a normal spleen was palpable. The peripheral pulses were equal in the upper and lower extremities. There was a 1.5 second capillary refill.
    The work-up after being transferred to the local hospital revealed a saturation of 68% and a hyperoxia test showed an increased in the saturation to 80%.
    The chest radiograph showed clear lung fields andno cardiomegaly.
    The electrocardiogram showed upright T waves in V1 and V2 and mild right ventricular hypertrophy.
    An arterial blood gas was normal. a dignosis of of cyanotic congenital heart disease was made, but the patient was also placed on intravenous antibiotics because of his age and possible co-existing sepsis.
    He was transported to a regional children’s hospital where an echocardiogram revealed the specific diagnosis of Tetralogy of Fallot. A cardiac catheterization was planned to determine anatomy, pressures and to plan probable surgery to increase pulmonary blood flow.

    Discussion
    Cyanosis is a blue coloring of the skin and mucous membranes caused by an increase concentration of reduced hemoglobin. This occurs at a critical level of about 5 g/100 ml of reduced hemoglobin.

    Cyanosis is caused by

    • Decreased arterial oxygen saturation
      • Inadequate alveolar ventilation
        • Airway obstruction
        • Structural changes in the lungs (e.g. pneumonia, hyaline membrane disease, etc.)
        • Central nervous system hypoventilation
        • Weakness of the respiratory muscles
      • Desaturated blood bypassing the lungs
        • Cyanotic congenital heart disease
        • Pulmonary arterio-venous fistulas
    • Increased capillary deoxygenation
      • Acrocyanosis of the newborn
      • Congestive heart failure
      • Shock
    • Abnormal hemoglobin
      • Carbon monoxide poisoning
      • Methemoglobinemia

    The hyperoxia test is a screening diagnostic test used to often determine if the cyanosis is caused by the circulatory or pulmonary systems. The infant is placed in room air and the saturation measured. The infant is then placed in 100% oxygen environment and the saturation is again measured.
    If the problem is in the lungs, the saturation should increase with supplemental oxygen.
    If the problem is caused by cardiac disease, the saturation should not improve with the supplemental oxygen. This is because there is still mixing of saturated and desaturated blood in the heart. The hyperoxia test is useful as a general test, but as each child’s cardiac anatomy may be different, the test may not show these results every time.

    Congenital heart disease occurs in ~10 /1000 live-born children. The incidence is higher in stillborn and spontaneous abortuses. The most common congenital heart disease is a ventricular septal defect and the most common cyanotic congenital heart defect is transposition of the great vessels.

    Common congenital heart disease incidence as a percentage of all congenital heart disease

    	Ventricular septal defect		27.1-42
    Atrial septal defect 6.8-11.7
    Patent ductus arteriosus 5.3-11 (excluding preterm infants)
    Transposition of the great vessels 3.5-5.3
    Tetralogy of Fallot 3.9-6.8
    Truncus arteriosus 0.7-1.7
    Total Anomalous Pulmonary Venous Return 0.6-1.7
    Hypoplastic right heart 1.4-3.2 (mainly tricuspid atresia and pulmonary atresia with intact ventricular septum)

    Learning Point
    As noted before, the anatomy of an child is highly individualized. But time courses for general symptom presentation can be considered for various congenital heart disease.

    Presents Almost Immediately at Birth

    • Transposition of the great vessels (D-transposition) – The aorta arises from the right ventricle and the pulmonary artery arises from the left ventricle forming parallel systemic and pulmonary systems. Communication between the systems is required for the infant to survive. These communications can be an atrial septal defect, patent foramen ovale, patent ductus arteriosus or combinations of these.
      D-transposition usually presents with severe cyanosis at birth.

    • Tricuspid atresia – There is no direct communication between the right atria and right ventricle. Blood must go from the right atrium to the left atrium by an atrial septal defect or patent foramen ovale. A patent ductus arteriosus is the source of blood flow to lungs. There are several variants of tricuspid atresia and associated lesions may determine the presentation.

    Presents in the Perinatal Period

    • Truncus arteriosus – A single great vessel leaves the heart to supply coronary artery flow, aortic flow and pulmonary flow. There is almost complete mixing of the systemic and pulmonary blood. The degree of cyanosis is dependent on the size of the pulmonary arteries and the magnitude of pulmonary blood flow.
    • Total anomalous pulmonary venous return – The pulmonary veins fail to connect normally to the left atrium. Alternate pathways direct flow to the right atrium and then across an atrial communication. The admixture of blood at the atrial level and the right to left atrial shunt result in the cyanosis. When this lesion presents at birth, it is because of obstruction to the pulmonary veins.
    • Tetralogy of Fallot (also known as a “TET” or “blue TET”) – The are four abnormalities are: ventricular septal defect, pulmonic stenosis, right ventricular hypertrophy and an overriding aorta. The amount of restriction through the right ventricular outflow tract determines the amount of pulmonary flow and influences the amount of right to left shunt across the ventricular septal defect. The degree of cyanosis is a reflection of the amount of pulmonary flow.

    Presents after the Perinatal Period

    • Tetralogy of Fallot (also known as a “pink Tetralogy” or “pink TET”) – The amount of restriction through the pulmonary valve and right ventricular outflow tract is less severe and there may be left-to-right shunting through the ventricular septal defect until pulmonary stenosis progresses.
      “Tet spells” occur when there is a provocation of a fall in systemic resistance and fixed pulmonary obstruction is present. At these times, the flow across the ventricular septal defect fecomes right to left and the patient has a cyanotic spell.
      The spells are characterized by tachypnea, cyanosis and a shorter outflow murmur. Treatment includes calming the child, and increasing the systemic vascular resistance (i.e. knee-to-chest position, volume influsion or sedation) by slowing the heart rate (beta-blocker therapy) to allow longer diastolic filling. Oxygen can also be administered to the infant but if resisted can actually be counterproductive.

    Questions for Further Discussion
    1. What are the common chest radiographic signs of congenital heart disease?
    2. What congenital heart diseases are associated with chromosomal abnormalities?
    3. What congenital heart diseases are associated with maternal medications?

    Related Cases

    To Learn More
    To view pediatric review articles on this topic from the past year check PubMed.

    Information prescriptions for patients can be found at MEDLINEplus for this topic: Congenital Heart Disease
    and at Pediatric Common Questions, Quick Answers for these topics:
    Congenital Heart Disease and Heart Murmurs and Arrhythmias.

    To view current news articles on this topic check Google News.

    Rudolph CD, et. al. Rudolph’s Pediatrics. 21st edit. McGraw-Hill, New York, NY. 2003:1780-81.

    Robertson J, Shilkofski N. The Harriet Lane Handbook. 17th edition. Elsevier Mosby Philadelphia, PA. 2005:159-210.

    Park MK. Pediatric Cardiology for Practitioners. 3rd edition. Mosby. St. Louis, MO. 1996;114-128.

    ACGME Competencies Highlighted by Case

  • Patient Care
    1. When interacting with patients and their families, the health care professional communicates effecively and demonstrates caring and respectful behaviors.
    2. Essential and accurate information about the patients is gathered.
    3. Informed decisions about diagnostic and therapeutic interventions based on patient information and preferences, up-to-date scientific evidence, and clinical judgment is made.
    4. Patient management plans are developed and carried out.
    7. All medical and invasive procedures considered essential for the area of practice are competency performed.
    8. Health care services aimed at preventing health problems or maintaining health are provided.
    9. Patient-focused case is provided by working with health care professionals, including those from other disciplines.

  • Medical Knowledge
    10. An investigatory and analytic thinking approach to the clinical situation is demonstrated.
    11. Basic and clinically supportive sciences appropriate to their discipline are known and applied.

  • Interpersonal and Communication Skills
    19. The health professional works effectively with others as a member or leader of a health care team or other professional group.

  • Systems Based Practice
    24. Cost-effective health care and resource allocation that does not compromise quality of care is practiced.

    Author
    Donna M. D’Alessandro, MD
    Associate Professor of Pediatrics, Children’s Hospital of Iowa
    Dr. D’Alessandro would also like to thank Dr. Jill Morriss, Professor of Clinical Pediatrics for her helpful suggestions in reviewing and improving this case.

    Date
    January 23, 2006

  • What are the Treatments for Persistant Cradle Cap?

    Patient Presentation
    A 2-year-old male came to clinic for his health maintenance examination. His mother has noticed that he still has cradle cap. She has tried baby shampoo, selenium sulfide shampoo, tar shampoos and mineral oil with scraping by a toothbrush.
    These treatments slightly improve the problem but it continues.
    The pertinent physical exam reveals a healthy toddler with some waxy, yellow, thick scale on the center of the scalp. The affected area is about 2 centimeters in diameter and is non-erythematous.
    The diagnosis of continued seborrheic dermatitis was made. He was referred to dermatology who recommended a short course of topical steroids to decrease the scale. Once the scale was controlled alternating use of baby shampoo and salicylic acid shampoo was recommended.
    If the scale returned, a short course topical steroids were recommended for control.
    The patient’s clinical course showed no scale after 3 weeks of daily topical steroid. The scale is well controlled with alternating baby and tar shampoos.

    Discussion
    Seborrheic Dermatitis or seborrhea is a scaly, crusty eruption usually of the face, scalp, post auricular, presternal and intertriginous areas of the skin.
    It commonly worsens with changes in humidity, seasons, or trauma. The cause is linked to Malassezia organisms and an abnormal immunological response with activated complement levels.
    It commonly occurs in the first few weeks of infancy and generally clears by 8-12 months of age. It can recur during puberty and adolescense.
    Cradle cap or infantile seborrheic dermatitis often occurs on the scalp and diaper area, but can spread to the face and back of the head. It has scales that are greasy, yellowish and thick.
    It is different from seborrheic dermatitis of adolescents and adults as it lacks the presence of follicular lesions.
    It is not pruritic and does not have the characteristics of atopic dermatitis.

    Learning Point
    The prognosis even without treatment is good as most cases of infantile seborrheic dermatitis clear within weeks. Complications include secondary bacterial or candidal infections.

    Treatment for infantile seborrhea includes:

    • Anti-seborrheic shampoos including alternating tar, salicyclic acid, zinc or selenium shampoos
    • Loosening of the scale by mineral oil or other similar oil with scrubbing several hours later.
    • Topical corticosteroids – low to medium potency, with or without sulfur or salicyclic acid

    Treatment for adolescent seborrhea includes:

    • Anti-seborrheic shampoos
    • Calcineurin inhibitors – pimecrolimus, tacrolimus
    • Topical corticosteroids
    • Antifungal medication – systemic medication may be helpful with recalcitrant cases

    Treatment for blepharitis (i.e. inflammation of the eyelids) includes:

    • Warm water compresses
    • Dilute baby shampoo or other non-irritating shampoo
    • Topical antifungal medications are controversial because of the location

    Questions for Further Discussion
    1. How does seborrhea differ from psoriasis?
    2. Is seborrhea related to atopic dermatitis?

    Related Cases

    To Learn More
    To view pediatric review articles on this topic from the past year check PubMed.

    Information prescriptions for patients can be found at MEDLINEplus for this topic: Dermatitis

    To view current news articles on this topic check Google News.

    Hurwitz S. Clinical Pediatric Dermatology. 2nd Edit. WB Saunders Co. Philadelphia PA. 1993;62-63.

    Selden S. Seborrheic Dermatitis. eMedicine.
    Available from the Internet at http://www.emedicine.com/derm/topic396.htm (rev. 9/13/05, cited 11/23/05).

    ACGME Competencies Highlighted by Case

  • Patient Care
    1. When interacting with patients and their families, the health care professional communicates effecively and demonstrates caring and respectful behaviors.
    2. Essential and accurate information about the patients is gathered.
    3. Informed decisions about diagnostic and therapeutic interventions based on patient information and preferences, up-to-date scientific evidence, and clinical judgment is made.
    4. Patient management plans are developed and carried out.
    5. Patients and their families are counseled and educated.
    9. Patient-focused case is provided by working with health care professionals, including those from other disciplines.

  • Medical Knowledge
    11. Basic and clinically supportive sciences appropriate to their discipline are known and applied.

  • Systems Based Practice
    24. Cost-effective health care and resource allocation that does not compromise quality of care is practiced.

    Author
    Donna M. D’Alessandro, MD
    Associate Professor of Pediatrics, Children’s Hospital of Iowa

    Date
    January 17, 2006

  • What Are the Classifications of Seizures?

    Patient Presentation
    A an 8 month-old female was referred for evaluation and treatment of episodes of sudden, jerking of her body such that she seems to collapse in half like a jack-knife. These occur multiple times a day and last for 5-30 seconds and are occurring more frequently.
    Three weeks ago she began having episodes of sudden crying episodes and over time her mother noticed that when she picked up the child, the baby would seem to twitch. The baby is described as more tired lately but has been drinking formula normally. She has been otherwise well.
    The past medical history revealed a full-term infant with normal pre- and perinatal history. She has received her regular well child care, but has been noted to be slow in her development.
    She smiled at 12 weeks, rolled over at 5-6 months, sits with support and makes vowel sounds. She has not lost developmental milestones.
    The family history noted family members with epilepsy and learning problems.
    The review of systems was normal including no fever, rashes, cough or upper respiratory tract infections.
    The pertinent physical exam showed a child who was afebrile with normal vital signs. She was 25-50% for weight and height. Head circumference was 10-25% and all were tracking normally. Her skin showed a small capillary hemangioma on her leg.
    Neurologically she appears sleepy and is somewhat difficult to arouse. Her cranial nerves III-XII are normal. Her deep tendon reflexes are normal with upward going toes bilaterally. She has normal tone and strength. Symmetric tonic neck reflex and palmar grasp primitive reflexes are elicited.
    During observed episodes she has flexion of the trunk and extremities that occurs suddenly and appears to cluster in frequency. The episodes last 10-30 seconds. The rest of the examination is normal.
    The work-up included an electroencephalogram (EEG) which showed hypsarrhythmia.
    The diagnosis of infantile spasms was made and adrenocorticotropic hormone was begun with great improvement of the seizures. Further evaluation, including evaluation for tuberous sclerosis, did not reveal an obvious cause for the infantile spams.

    Discussion
    West syndrome includes infantile spams, hypsarrhythmia on EEG and mental retardation. It usually occurs in infants < 12 months with a peak at 4-6 months. Hypsarrhythmia is a chaotic EEG abnormality that has random, high-voltage slow waves and spikes that arise from multiple foci and spread to all cortical areas.
    It was first described in 1841 by Dr. W. J. West where he describes the seizures of his own son, James Edwin West, who showed the first symptoms at the age of about four months and lived until ~ age 20.
    West described the seizures "…cause a complete heaving of the head forward towards his knees, and then immediately relaxing into the upright position…these bowings and relaxings would be repeated alternately at intervals of a few seconds, and repeated from ten to twenty or more times at each attack, which attack would not continue more than two or three minutes; he sometimes has two, three or more attacks in the day."
    Dr. West did not know what caused the seizures but hypothesized that "… it depended on some irritaiton of the nervous system from teething…." He tried treating his son with leeches, cold application to his head, calomel purgatives, lancing of his gums, opium, syrup of poppies and castor oil. He also sought consultation with preeminant physicians who knew of a total of 6 other cases and referred to them as "salaam convulsions." They also believed they were related to teething.

    Infantile spasms are classifed by suspected etiology:

    • Idiopathic – patient has normal development before the spasms occur and no obvious or suspected cause is identified

    • Cryptogenic – no cause is identifed but a cause is suspected
    • Symptomatic – almost any problem which causes brain damage can be associated with infantile spasms. Tuberous sclerosis is the most common identified cause of infantile spasms (10-30% of prenatal cases), therefore evaluation for tuberous sclerosis is indicated.

    Infantile spasms are also commonly associated with Lennox-Gastalt syndromewhich is a syndrome characterized by multiple types of seizures, mental retardation or regression, and abnormal EEG with generalized slow spike-and-wave discharges. It is very difficult to treat.

    Learning Point
    Classification by the International League Against Epilepsy include:

    • Partial seizures or seizures with a focal onset
      • Simple partial seizures (consciousness unimpaired)
        • with motor signs

        • with somatosensory or special sensory symptoms
        • with autonomic symptoms or signs
        • with psychic signs
      • Complex partial seizures (consciousness impaired)

        • beginning as a simple partial seizure

          • with automatisms

          • without automatisms
        • impaired consciousness at the beginning of the seizure

          • with automatisms

          • without automatisms
      • Partial seizure which evolve into secondarily generalized seizure (e.g. Jacksonian march)
    • Generalized seizures
      • Absence seizures – briefly unaware without postictal impairment
      • Myoclonic seizures – brief repetitive symetric muscle contractions or loss of tone – which includes infantile spasms
      • Clonic seizures – rhymic jerking with flexor spasms of muscles
      • Tonic seizures – sustained muscle contraction
      • Tonic-clonic seizures
      • Atonic seizures – sudden loss of muscle tone
    • Unclassified seizures

    Initial treatment for partial seizures or generalized tonic-clonic seizures usually is carbamazepine or valproic acid.
    Initial treament for absence seizures is often ethosuxamide and for infantile spasms is adenocorticotropic hormone.

    Questions for Further Discussion
    1. What are the normal neurological primitive reflexes and at what age should they disappear by?
    2. What is the long term outcome of patients with infantile spasms or Lennox-Gastalt syndrome?

    Related Cases

    To Learn More
    To view pediatric review articles on this topic from the past year check PubMed.

    Information prescriptions for patients can be found at MEDLINEplus for this topic: Epilepsy
    and at Pediatric Common Questions, Quick Answers for these topics: Epileptic Seizure and Febrile Seizure.

    To view current news articles on this topic check Google News.

    Robertson J, Shilkofski N. The Harriet Lane Handbook. 17th. Edit. Mosby Publications: St. Louis. 2005:515.

    Glauser TA, Morita DA. Lennox-Gastaut Syndrome. eMedicine.
    Available from the Internet at http://www.emedicine.com/neuro/topic186.htm (rev.1/30/2002, cited 11/17/2005).

    Glauser TA, Morita DA. Infantile Spasms (West Syndrome). eMedicine.
    Available from the Internet at http://www.emedicine.com/neuro/topic171.htm (rev. 6/21/2002, cited 11/17/2002).

    Who Named It? William James West. Available from the Internet at http://www.whonamedit.com/doctor.cfm/2676.html (cited 11/17/2005).

    ACGME Competencies Highlighted by Case

  • Patient Care
    1. When interacting with patients and their families, the health care professional communicates effecively and demonstrates caring and respectful behaviors.
    2. Essential and accurate information about the patients is gathered.
    3. Informed decisions about diagnostic and therapeutic interventions based on patient information and preferences, up-to-date scientific evidence, and clinical judgment is made.
    4. Patient management plans are developed and carried out.

  • Medical Knowledge
    10. An investigatory and analytic thinking approach to the clinical situation is demonstrated.
    11. Basic and clinically supportive sciences appropriate to their discipline are known and applied.

    Author
    Donna M. D’Alessandro, MD
    Associate Professor of Pediatrics, Children’s Hospital of Iowa