21 Flashcards
Petechiae and purpura can be caused by 5
One approach to thinking about a clinical problem is to consider possible underlying mechanisms. Petechiae and purpura can be caused by:
Trauma
Platelet deficiency or dysfunction (e.g. immune-mediated thrombocytopenia, bone marrow infiltration or suppression, malignancy)
Coagulation abnormalities (e.g. hereditary or acquired clotting-factor deficiencies)
Vascular fragility (e.g., immune-mediated vasculitis)
Combinations of the above (e.g., infection causing coagulation abnormalities, vascular fragility, platelet consumption)
Diff dx for brushing and leg pain 9
Coagulation disorder
A coagulation disorder may present with petechiae or superficial bruising, but more often presents with easy bruising in deep tissues or hemarthrosis.
Bleeding disorders (hemophilias, von Willebrand’s disease) are characterized by easy bruising in response to minor trauma. Spontaneous superficial bruising is less common.
Hemophilias may present with painful bleeding into joints (hemarthrosis).
Children with coagulation disorders often have a positive family history and/or personal history of bleeding (e.g., after trauma, immunizations, circumcision, dental work).
Henoch-Schönlein purpura (HSP)
HSP is a self-limited, IgA-mediated, small vessel vasculitis that typically involves the skin, GI tract, joints, and kidneys.
Often presents in an otherwise well appearing child with bruising and leg pain (due to arthritis).
In roughly 50% of cases, a URI precedes the diagnosis of HSP.
Idiopathic thrombocytopenic purpura (ITP)
Often presents with asymptomatic petechiae.
A nonspecific URI precedes ITP more than 50% of the time.
Leukemia
Usually presents with constitutional symptoms such as fever, malaise and weight loss.
Bone pain is also a common presentation of leukemia in children. The pain results from infiltration of the bone marrow by malignant cell.
Petechiae can be caused by thrombocytopenia due to bone marrow replacement by malignant cells.
Viral infection
Some viruses, such as enteroviruses, may present with a petechial rash.
Children usually have a low-grade fever.
Other constitutional complaints may be present or absent.
Prominent coughing and/or vomiting can also cause petechiae, generally above the nipple line.
Bacterial endocarditis
Typical presenting complaints are fever, fatigue, and weight loss.
A petechial rash is commonly seen.
Bruising is not characteristic.
Fever is usually present, but may be low-grade.
Meningococcal septiciemia
Children with meningococcal septiciemia may present with petechiae and purpura, which can be confused with bruising.
While the early stages of meningococcemia may have only mild symptoms, by the time the hemorrhagic rash appears, patients are usually very ill appearing and require emergent care.
Rocky Mountain spotted fever (RMSF)
The rash of RMSF is often petechial, and starts on the extremities before moving centrally.
Fever is a hallmark of RMSF.
Systemic lupus erythematosus (SLE)
The rash of SLE can be variable.
More common in older children and in girls.
SLE often presents with constitutional symptoms such as fever and malaise.
Arthralgia vs arthritis
The exam findings in this case suggest arthralgia. Arthralgia refers to pain in or around the joint without signs of synovitis.
The term arthritis is used in the presence of true synovitis, defined as either joint swelling or joint pain with limitation of motion on exam.
Findings in hsp itp and leukemia
Findings in HSP, ITP, and Leukemia
Certain rash distributions suggest specific diagnoses.
HSP- affect skin, gi, kidneys, joints
The rash of HSP is somewhat unique in its tendency to involve primarily the lower extremities.
HSP often causes a periarticular vasculitis presenting as arthritis or arthralgia.
HSP is not associated with splenomegaly. A palpable spleen in a child with suspected HSP should prompt evaluation for other causes.
ITP
ITP is not associated with splenomegaly. If discovered in a child with thrombocytopenia, splenomegaly should prompt evaluation for other processes, including leukemia or other malignancy.
Leukemia
Bone pain secondary to bone marrow expansion may cause pain localized to the joints.
Splenomegaly and lymphadenopathy are common findings in leukemia.
Evaluation of suspected HSP 3
Platelet count
The platelet count is essential to determine whether this is non-thrombocytopenic (HSP) or thrombocytopenic (ITP or leukemia) purpura.
The results of the hemoglobin and leukocyte count can provide helpful information when there is concern for leukemia.
Urinalysis
With HSP it is important to determine whether the patient has renal involvement.
A urinalysis will detect hematuria and/or proteinuria.
BUN and creatinine
If either hematuria or proteinuria is present, a BUN and creatinine are indicated to determine the extent of renal disease.
HSP Epi Symptoms Complications Tx
HSP (also known as anaphylactoid purpura) is a self-limited, IgA-mediated, small vessel vasculitis that typically involves the skin, GI tract, joints, and kidneys.
Epidemiology
HSP is the most commonly diagnosed form of vasculitis in children (about 50% of cases) .
Signs and Symptoms
The hallmark of HSP is non-thrombocytopenic purpura.
One-third of children with HSP have renal involvement, the most common manifestation of which is hematuria. Renal involvement is less common in children under two years of age, occurring in about 25% in that age group).
Arthritis or arthralgia, mainly of the knees and ankles, is seen in about 75% of children with HSP.
Colicky abdominal pain is present in 65% of patients. About 50% of children with HSP may develop intestinal bleeding, with guiaic positive stool..
Two-thirds of patients report a recent upper respiratory tract infection.
Complications
About 5% of children with HSP progress to chronic renal failure. Fewer than 1% will develop end-stage renal disease.
Although HSP is considered a benign childhood disease, it occasionally requires hospitalization for management of severe abdominal pain, GI bleeding, intussusception, and renal involvement.
Treatment
Treatment with steroids remains controversial. However, a recent analysis suggests early corticosteroids in hospitalized children with HSP may confer benefits in reducing gastrointestinal manifestations. Systematic reviews have not demonstrated a consistent benefit for corticosteroids in preventing serious renal involvement. There is a need for a high-quality multicenter, randomized controlled trial to help us understand the potential benefits of early corticosteroids for children HSP.
Idiopathic thrombocytopenic purpura MOA
Lab finding
Tx
ITP is caused by the binding of an antiplatelet antibody to the platelet surface, leading to removal and destruction of platelets in the spleen and liver. It is the most common cause of isolated thrombocytopenia in otherwise healthy children.
Platelets 20,000 or less
IVIG
HSP
Prognosis
Follow up
Meds
Prognosis
HSP usually lasts a month or so and goes away on its own without any treatment.
Follow-up
Usually all that is required is to check repeat urine samples to monitor kidney inflammation and to follow blood pressure.
Acetaminophen for pain
Intussusception Pathophys and pathophys in HSP Presentation Dx Tx
Intussusception is the most common form of bowel obstruction in children between 6 months and 6 years of age.
Overall incidence: 1-4 cases per 1,000 live births
Eighty percent of cases occur in children under 2
Boys are affected more often than girls
Pathophysiology
Intussusception occurs when a proximal segment of bowel invaginates or telescopes into the distal segment adjacent. The accompanying mesentery becomes entrapped, causing vascular compression and eventual ischemia.
Most cases of intussusception do not involve a discrete, identifiable lead point. Hypertrophied intestinal lymphoid tissue (e.g., in response to a concurrent viral infection) has been suggested as a possible trigger.
Occasionally, a pathological lead point (e.g., polyp, Meckel’s diverticulum) starts the telescoping process. Intussusception in HSP likely begins at points of intestinal edema or submucosal hemorrhage.
Idiopathic intussusception (in which there is no identifiable lead point) occurs in otherwise healthy infants and toddlers. The majority of cases involve the ileocecal junction.
Intussusception in HSP is usually ileo-ileal.
Presentation
The classic presentation of intussusception includes:
Paroxysms of severe abdominal pain with inconsolable crying
Passage of “currant jelly” stool containing blood and mucus
Palpation of a “sausage-shaped” mass in the right abdomen
A minority of patients present with the classic triad of findings. Diagnosis requires a high index of suspicion. Additional signs and symptoms may include vomiting (bilious or non-bilious), lethargy and a toxic appearance, with or without signs of pain.
Diagnosis and Treatment
The standard approach to diagnosis and treatment of idiopathic intussusception is to perform an air or barium enema.
Ultrasound has increasing utility in the initial evaluation.
Once the intussusception is visualized, the telescoped segment of bowel is reduced by air or hydrostatic pressure. Occasionally, the procedure is unsuccessful and patients require surgical reduction.
Because intussusception occurring in HSP is usually ileo-ileal, not ileo-colic, it will not be reduced by air or barium enema. Diagnosis requires abdominal ultrasound, and treatment is generally surgical.
HSP recurrence
The recurrence rate for HSP is about 30%. Symptoms may return weeks to many months after the first episode.
Like the initial episode, a recurrence may start with abdominal pain, rather than rash, so it is important to keep HSP in mind if a patient has significant abdominal pain in the future.
If a recurrence does occur, it is important to recheck the urine to evaluate for renal involvement.
