A well-appearing 6-year-old presents to your office with a chief complaint of bruising. The parents report that the child had a cold 2 weeks ago but completely recovered. The child is sitting on the examining table, in no distress, discussing her favorite cartoons. On examination, you find mucosal bleeding and bruises on the child's arms and chest. You order a complete blood count (CBC) that has the following results: WBC 12,000, hemoglobin 11 g/dL, and a platelet count of 45,000.What is the most likely cause of this child's bleeding and bruising?
Answer(s): A
The hallmark of immune (also known as idiopathic) thrombocytopenia purpura (ITP) is the otherwise healthy appearing child with isolated thrombocytopenia. ITP is the most common cause of isolated thrombocytopenia in childhood. It occurs with equal frequency in both boys and girls. The presence of thrombocytopenia in a patient with otherwise normal cell lines, and a normal physical examination is enough to make the diagnosis, so further evaluation, such as a bone marrow biopsy, is unnecessary. Which children to treat and which treatment to use are areas of controversy in the management of ITP. Most acute ITP will resolve spontaneously, so many will recommend observation for children who appear well, are asymptomatic, and have platelet counts above 30,000. Platelet transfusions should be reserved only in the instance of ongoing or imminent bleeding. When a decision is made to treat, usually when the platelet count falls below 20,000, there are several options available. Treatment involves using IVIG, steroids, anti-D immunoglobulins, or combinations thereof. Combinations of medications may work synergistically. Prednisone is often used initially, as it can be given orally and is inexpensive. Typically, it will be tapered over 2 weeks to 3 months. By using combination therapy when needed, splenectomy can be avoided in the vast majority of cases. When it is necessary, it should be delayed, if at all possible, for at least a year after diagnosis.
A well-appearing 6-year-old presents to your office with a chief complaint of bruising. The parents report that the child had a cold 2 weeks ago but completely recovered. The child is sitting on the examining table, in no distress, discussing her favorite cartoons. On examination, you find mucosal bleeding and bruises on the child's arms and chest. You order a complete blood count (CBC) that has the following results: WBC 12,000, hemoglobin 11 g/dL, and a platelet count of 45,000.After discussing various options with a regional pediatric hematologist and the patient's parents, your most appropriate initial management would be which of the following?
Answer(s): C
A well-appearing 6-year-old presents to your office with a chief complaint of bruising. The parents report that the child had a cold 2 weeks ago but completely recovered. The child is sitting on the examining table, in no distress, discussing her favorite cartoons. On examination, you find mucosal bleeding and bruises on the child's arms and chest. You order a complete blood count (CBC) that has the following results: WBC 12,000, hemoglobin 11 g/dL, and a platelet count of 45,000.Following your initial evaluation and treatment, you see the child for follow-up in 1 week. She continues to appear well but still has obvious purpura and her platelet count is now 17,000. All other cell lines are normal. Of the options listed below, what is your most appropriate management at this time?
Answer(s): D
A 4-year-old child is brought to your office because of a sudden onset of irritability, weakness, and pallor. The mother tells you that both of her children have been experiencing episodes of vomiting and diarrhea. Your physical examination reveals a blood pressure of 115/80, dry mucus membranes, petechiae, and diffuse abdominal pain. The following laboratory work is obtained:Urinalysis: microscopic hematuria and proteinuria Blood urea nitrogen (BUN)/creatinine (Cr):20/1.0 mg/dLHemoglobin: 7 g/dLPeripheral blood smear: fragmented RBCsProthrombin time (PT), partial thromboplastin time (PTT): normal Coombs' test: negativeWhat is the most likely diagnosis?
Answer(s): E
HUS is, as the name implies, the combination of a microangiopathic hemolytic anemia and acute renal failure. It is commonly associated with E. coli O157/H7 gastroenteritis. HUS is one of the most common causes of acquired renal failure in children.
A mildly mentally retarded 9-year-old girl is brought to your office for acne. On examination, she does not actually have acne but has small flesh colored papules along her nasolabial fold. Her past history is significant for having had a first (afebrile) seizure last year. The mother reminds you that she has a faint birthmark on her hip that is pale and becomes more prominent in the summer, when the child's skin tans. Examination of this area reveals a 5-cm oval patch that is hypopigmented. Which condition would she most likely have?
Children with tuberous sclerosis (tuberous sclerosis complex, TSC) can develop nasolabial fold angiofibromas (commonly referred to adenoma sebaceum). These can be mistaken for acne in an adolescent and is seen in over 80% of adolescents with TSC. Other cutaneous findings include peri- and subungual fibromas, ash leaf spots (hypomelanocytic macules), and shagreen patches. Skin findings are seen in 75% of cases of tuberous sclerosis. Tuberous sclerosis can also have CNS cortical defects and "tubers," which may be foci of seizure activity. The "tubers" have a classic periventricular distribution. Mental retardation is very common in varying degrees. Sturge-Weber syndrome (also known as leptomeningeal angiomatosis) is a port wine stain, typically with V1 or V2 distribution, with an underlying leptomeningeal blood vessel dysplasia. These dysplastic vessels will typically result in an underlying cortical atrophy. This cortical atrophy can be a nidus for seizures and can be seen on a CT scan of the head. Neurofibromatosis, type 1 is polymorphous neurocutaneous syndrome. The most common findings are café au lait spots, which may be present at birth and worsen during puberty. Beckwith-Wiedemann syndrome and CHARGE association are discussed further in explanations 44 and 45.
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