11 Flashcards
Dx and tx of group a strep pharyngitis
Initiating abx and selection of abx
Pharyngitis secondary to group A beta-hemolytic Streptococcus (Streptococcus pyogenes) (GAS) is a common pediatric infection. Though the acute illness is usually self-limited, diagnosis and treatment are important to prevent potential serious sequelae, especially rheumatic fever.
Diagnosis
Patients in whom the diagnosis is suspected should have diagnostic testing performed.
A “rapid strep” test detects a streptococcal antigen from a throat swab obtained by swabbing the tonsils and posterior pharynx. This test is highly specific, but there is variable sensitivity.
A positive rapid strep test generally does not require any further laboratory confirmation; however, a negative result should be confirmed by standard throat culture.
Initiating Antibiotics
Ideally, there should be documentation of infection with GAS prior to initiating antibiotics. However, some physicians will treat patients with antibiotics based on a clinical diagnosis of GAS pending results of the culture. Others will wait for culture results in the setting of a negative rapid strep test.
Appropriate antibiotics started within nine days from the start of the acute illness will prevent acute rheumatic fever.
Antibiotic Selection
Although penicillin is the drug of choice for GAS pharyngitis, the suspension form does not have a pleasant taste. Therefore, many physicians opt for oral amoxicillin, which is more palatable.
In a child who refuses oral medications or when adherence to a 10-day regimen will be difficult for the family, a single intramuscular injection of penicillin may be the best option.
Diff dx for fever and rash - 7
Disease Description Typical features from H&P
Systemic-onset juvenile idiopathic arthritis (JIA) - autoimmune disorder manifesting as morning stiffness
One of a group of common rheumatic diseases subdivided into:
Oligoarthritis (or pauciarticular disease) - 4 or fewer joints and uveitis is common ( most common presentation),
Polyarthritis - 5 or more joints,
or
Systemic-onset disease (also called Still’s disease)
Prolonged fever could suggest Still’s disease
Rash - stills dis has salmon colored macular rash
Arthritis (although active arthritis in Still’s disease often presents months to years after onset)
Visceral involvement (e.g., hepatosplenomegaly, lymphadenitis, serositis) - stills dis
Kawasaki disease Vasculitis Fever > 5 days Nonpurulent conjunctivitis (may have cleared prior to presentation) Rash Swelling and erythema of extremities CRASH and BURN mnemonic conjunctivitis, rash, adenopathy, strawberry tongue, hands and feet swollen and peeling, fever
Osteomyelitis/septic joint Bacterial infection (80% of cases occur in the lower extremities) Low-grade fever Painful walking (if in lower extremity)
Rocky Mountain spotted fever (RMSF) Tick-borne bacterial infection (Rickettsia rickettsii)
Fever
Headache
Rash (typically starts on ankles and wrists and progresses centrally and to palms and soles*; may be maculopapular at first, quickly becoming petechial; in 5% of cases, there may be no rash)
Myalgias
*Other causes of rash involving palms and soles: Kawasaki disease, enteroviruses, syphilis.
Scarlet fever
Group A Streptococcus infection
Fever (generally < 5 days)
A diffuse, erythematous, finely papular rash (described as having a “sandpaper” texture) is pathognomonic
Rash often begins at neck, axillae, and groin and then spreads over trunk and extremities, typically resolving within four or five days
Stevens-Johnson syndrome A mucocutaneous disorder caused by a hypersensitivity reaction to medications, infections, or other illnesses
Severe, pruritic rash (erythema multiforme)
Fever (not expected to last 7 days)
Mucosal changes (e.g., stomatitis)
Conjunctivitis
Viral syndrome (enterovirus)
Covers wide variety of viral infections Fever lasting 3-5 days (but not a prolonged high fever)
Non-descript rash (enteroviruses can cause rash on palms and soles)
Rash is not painful and should not cause refusal to walk
Rash assoc with fever - 7
Enterovirus
Usually erythematous and maculopapular, and may involve the palms and soles. Infrequently, it can be petechial.
In hand-foot-and-mouth disease (caused by Coxsackie virus), presents as a vesicular rash on the hands and feet and with ulcers in the mouth.
Usually seen in late summer and early fall.
While the fever associated with enteroviruses may be high, it usually lasts only a few days.
Erythema infectiosum
Also called fifth disease, this is caused by parvovirus B19.
There is frequently an associated low-grade fever (37.8-38.3 degrees C, or 100-101 degrees F), with a rash appearing seven to ten days later.
The characteristic rash starts as facial erythema-the “slapped cheek” appearance. This can spread to the trunk and have an erythematous macular appearance. Central clearing of the rash appears, giving a lacy appearance.
The rash often lasts longest on the extremities, where it has a lacy, reticular appearance.
People with fifth disease can also develop pain and swelling in their joints (polyarthropathy syndrome).
Individuals with underlying immune deficiencies who are exposed to this virus are at risk for developing aplastic anemia.
Measles
After a prodrome of fever (over 38.3 C, or 101 F), cough, coryza, and conjunctivitis, this maculopapular rash starts on the neck, behind the ears, and along the hairline.
The rash spreads downward, reaching the feet in two or three days.
The initial rash appears on the buccal mucosa as red lesions with bluish white spots in the center (known as Koplik spots). These have frequently disappeared by the time the patient presents to medical attention.
Immunization is very effective in preventing this infection.
Meningococcemia
Caused by the bacteria Neisseria meningitidis, onset is abrupt and accompanied by fever, chills, malaise, and prostration.
The initial rash may be urticarial, maculopapular, or petechial (marked by small, purplish, hemorrhagic spots).
In fulminant cases, it can become purpuric, marked by large hemorrhages into the skin.
Immunization is effective in preventing this infection.
Roseola
This macular or maculopapular rash, also called exanthem subitum, starts on the trunk and spreads to the arms and neck.
There is usually less involvement of the face and legs.
The rash is preceded by three or four days of high fevers, which end as the rash appears.
Usually seen in children less than two years old.
Scarlet fever
This rash, caused by infection with group A Streptococcus, consists of very fine papules, often described as feeling like sandpaper.
It is erythematous, but blanches.
The rash starts in the groin, axillae, and neck, but rapidly spreads.
The fever can be high, and the disease is usually self-limited, lasting less than 10 days.
NO conjunctivitis and normal lips and no painful extremities
It is important to treat with antibiotics to prevent non-suppurative complications of strep, including rheumatic fever.
Varicella
The rash, also known as chicken pox, starts on the trunk and spreads to the extremities and head.
Each lesion progresses from an erythematous macule to papule to vesicle to pustule, and then crusts over.
Lesions at various stages of development are seen in the same area of the body.
There is usually a mild fever.
The disease is self-limited, lasting about a week.
Immunization is effective in preventing this infection.
Causes of unilateral cervical LAD - 5
In addition to Kawasaki disease and a reactive node from an oral inflammatory or infectious process, the following can all cause unilateral cervical lymphadenopathy:
Bacterial cervical adenitis
Typically seen in children ages one to five years with a history of a recent upper respiratory tract infection.
Staphylococcus aureus and Streptococcus pyogenes are the organisms most commonly identified.
Patients may have high fevers and a toxic appearance.
Overlying cellulitis and development of fluctuance are common.
Cat scratch disease
Infections caused by the bacterium Bartonella henselae can be asymptomatic or symptomatic.
The infection usually is introduced by a scratch from a cat or kitten, with subsequent infection of the node or nodes draining that site.
The site most commonly involved is the axilla, followed by cervical, submandibular, and inguinal areas.
Usually a self-limited disease, with regression of the lymph node in four to six weeks.
Mycobacterial infection
Mycobacterial infections can cause diffuse lymphadenopathy or isolated lymphadenitis.
Lymphadenitis is the most common manifestation of nontuberculous mycobacteria in children, with a peak age of presentation of 2 to 4 years.
Tuberculosis is the most common cause of mycobacterial lymphadenitis in children over 12 years of age.
Children with these infections usually appear well with minimal if any constitutional signs and symptoms.
The overlying skin may be erythematous initially, but left untreated often becomes violaceous as the nodes enlarge.
Nodes may rupture through the skin, resulting in a draining sinus tract.
Treatment is surgical excision, as incision and drainage can also result in a sinus tract.
Dx criteria for Kawasaki
Lab evaluation of Kawasaki
In addition to high fever for at least five days, four of the following five criteria are needed for a diagnosis of Kawasaki disease:
Changes in oral mucosa Extremity changes (redness/swelling) Unilateral cervical lymphadenopathy Rash Conjunctivitis The one least likely to be present is cervical adenopathy.
The final criterion is that there is no other apparent cause for the presentation (i.e., a child presenting with an obvious site of infection, even if meeting all criteria for Kawasaki, cannot be given the diagnosis).
Though irritability is very common, it is not part of the diagnostic criteria.
CBC with differential
A CBC with differential will help evaluate for possible infection or inflammatory response. It is also useful to evaluate for possible anemia, thrombocytopenia or thrombocytosis, any of which could be present in this patient. Typical CBC findings in a patient with Kawasaki disease:
WBC: The white blood count is usually elevated, with a predominance of neutrophils.
Hbg/Hct: A normochromic, normocytic anemia is common.
MCV: The MCV is usually normal.
Platelets: The markedly elevated platelet count associated with Kawasaki disease is usually not seen until the second week of the illness.
Blood culture
Although the clinical course is long for a bacteremic illnesses, the height of the fever and the clinical appearance of the patient justify obtaining a culture.
Liver enzymes
Liver enzymes can be elevated in a number of conditions on the differential, including both Kawasaki disease and Stevens-Johnson syndrome. Although this is an important test to obtain, it is of little benefit in narrowing your diagnosis in this case. Serum albumin level is frequently low in Kawasaki disease.
Acute phase reactants
There is great debate in the role of acute phase reactants (erythrocyte sedimentation rate [ESR] or C-reactive protein [CRP]). Their lack of specificity limits their utility for diagnostic purposes, though they can lend support for and against some diagnoses. They frequently play a more useful role in following a disease process.
In this case, a negative ESR would argue strongly against Kawasaki disease. The persistence of an elevated ESR after the fever has subsided can help to distinguish Kawasaki disease from other infectious rash/fever illnesses.
Urinalysis
A sterile pyuria, secondary to a sterile urethritis, is associated with Kawasaki disease. A clean-catch urine is likely to show white cells, whereas a catheterized urine may not (because the white cells come from the urethra).
Complications of Kawasaki
The complications associated with Kawasaki disease—and the approximate percentages of patients who develop these complications—are as follows:
Complication Percentage of KD Patients Who Experience
Central nervous system manifestations (including irritability, lethargy, aseptic meningitis)
90%
Coronary artery aneurysm 20-25% of untreated patients
Liver dysfunction 40%
Arthritis 30%
Hydrops of the gallbladder 10%
Of these, the greatest risk is the development of coronary aneurysms. The main purpose of treatment is to minimize this risk.
Timing
Aneurysms may be present by the end of the first week, but usually present later, almost always within four weeks of the onset of the disease.
Monitoring
All patients should receive an echocardiogram during the acute phase, both to look for the presence of aneurysms and to provide a baseline for future comparison.
Tx of Kawasaki
F/u protocol
Aspirin and intravenous immune globulin (IVIG) have been the standard therapy for Kawasaki disease for many years.
Aspirin
High-dose aspirin (80-100 mg/kg/day, divided into four doses) is administered for its anti-inflammatory properties.
Aspirin shortens the febrile course of the illness but has no effect on the development of aneurysm.
Following defervescence, low-dose aspirin (3-5 mg/kg/day given in a single dose) is administered for its anti-platelet effects.
Aspirin is discontinued altogether after a total of six to eight weeks if no coronary artery changes are seen in follow-up echocardiograms. If there are coronary artery abnormalities, low dose aspirin is continued indefinitely as an anti-platelet agent.
Aspirin and Reye syndrome: Children taking aspirin are at risk for experiencing Reye syndrome (a potentially fatal illness that causes multi-organ damage) if infected with certain viruses, including influenza virus A or B; therefore, physicians should be particularly vigilant about recommending influenza vaccination for children receiving long-term aspirin therapy.
IVIG
The use of IVIG in Kawasaki disease has decreased the incidence of coronary artery aneurysms from 20-25% to 2-4%.
A single dose of IVIG at a dose of 2 g/kg administered over ten to twelve hours has been shown to be more effective in reducing the risk of coronary artery aneurysms than multiple lower doses
Other antipyretics are usually not effective for fever control. Furthermore, use of ibuprofen has been shown to antagonize the irreversible platelet inhibition induced by aspirin and therefore should be avoided in children with coronary aneurysms taking aspirin for its antiplatelet effects.
Antibiotics have not been shown to have any effect on the clinical course.
The role of steroids is unclear. For years, steroids were felt to have no role, or even to be detrimental. Newer studies suggest that they may have a role in the acute management, and additional information is needed
Early cardiology follow-up with a repeat echocardiogram is needed. In Kawasaki disease, if coronary artery aneurysms develop, they usually do so within four weeks of the acute illness, so a follow-up visit at one to two weeks is recommended.
