Download Persistent Septic Arthritis and New Pulmonary Opacities in an

Clinico-pathological case 1
[Trinity College Dublin]
Clinical summary:
A 66-year-old, emaciated man was admitted on the 19/06 from a
nursing home facility with a 2 day history of increasing confusion.
He had been under continuous medical care in the nursing home for
three months when he was admitted for a complaint of "feeling bad".
There was a history of intravenous drug use (heroin), smoking crack
cocaine, and hepatitis C, but he was HIV negative.
He was afebrile.
The white blood cell count was 8.3x109/L.
End-stage renal disease (membranoproliferative glomerulonephritis
thought to be secondary to hepatitis C) requiring hemodialysis, R
knee and L wrist septic arthritis (Staph aureus and Strep
pneumoniae), and anaemia (Hct 28%) were diagnosed.
Blood cultures were also positive for Staph aureus, and he was
treated with flucloxacillin and gentamicin. The course was
complicated by recurrent line infections and fasciitis.
A trans-oesophageal echocardiogram showed no vegetations in the
heart. In mid May, he was transferred to a nursing home for
continued care.
On admission from the nursing home, his observations were as
follows:
T 98.9°, HR 80/min, RR 26/min, BP 144/83, and O2 saturation of 96%
on room air. Lungs were clear. No cardiac murmurs were heard. The
R knee and L wrist were again swollen.
Laboratory values were:
WBC 18x109/L, Hct 30%, and platelets 187x109/L.
A blood culture yielded gram positive cocci.
Vancomycin was begun.
QUESTIONS
Q1. What is the differential diagnosis in this case?
Q2. What clinical investigations would you perform?
Q3. What organism was most likely identified in the blood
culture?
Q4. Discuss the antibiotic policy in this patient.
A trans-oesophageal echocardiogram was performed, and a chest
radiograph was taken.
Trans-oesophageal Echocardiogram
On the 22/06, a crosssectional, two-dimensional
echocardiographic view of
the aortic and pulmonic
(PV) valves showed
thickening of the leaflets of
the PV and one of two
pedunculated vegetations
that prolapsed 3 cm into
the pulmonary artery
during systole. There was
no valvar insufficiency.
The tic marks at the edge
of the photograph are 1 cm
apart. Landmarks are
indicated on the same
photo below.
RV = right ventricular
chamber. PV = thickened
pulmonic valve. V and 2
arrows = vegetation on
stalk during systole. AO =
aorta. The small arrow
below AO indicates a
normal, thin aortic valve
leaflet. The arrowheads
indicate the wall of the
pulmonary artery trunk.
The patient was not considered to be a candidate for a surgical
procedure.
QUESTIONS
Q5. What is the cause of the vegetations in the heart?
Q6. Comment on the location of the vegetations.
Q7. Can you list the causes of heart valve vegetations?
Radiographic Findings
On the 26/06, a frontal CXR film showing the right lung demonstrated
multiple areas of mass-like consolidation, at least two of which
showed central cavitation. There was a small right effusion. The left
lung appeared normal.
The largest area of consolidation is at the
right lung base (lower arrow).
Superior to it is another mass-like
consolidation containing a central cavity. A
smaller mass-like consolidation is present in
the right upper lobe (upper arrow). To its
right is a well-formed cavity of approximately
the same size.
QUESTIONS
Q8. What are the causes of the lung consolidation?
Q9. What are the causes of the lung cavitations?
Q10. How would you further investigate these lesions?
Bacteremia persisted, thrombocytopenia developed, and he
remained confused.
He was found dead on the 30/06.
An autopsy was performed.
Autopsy Findings
A serosanguineous pleural effusion (300 ml) was present on the right
side. The heart was enlarged (380 g, normal 300 g). Look at each of
the following photos and explain what has happened.
A. Valves were normal except for the
pulmonic, which is shown here.
Compare it with an example of a
normal pulmonic valve below (B).
One commissure is indicated at the
arrow.
B. Normal pulmonic valve. Note the
thin, translucent cusps and normal
commissures.
QUESTION
Q11. What is the lesion on the pulmonic valve?
Answer: The pulmonic valve had large vegetations, about 2 cm in
diameter, on each of 2 cusps. They were very friable, and one (on
the leaflet to the right of the arrow) was dislodged before the photo
was taken, revealing a hole, 5 x 3 mm in diameter (not shown), in the
cusp. The vegetation that is present (anterior leaflet) obscures the
commissure and has spread to the wall of the pulmonary artery. No
pedunculated portion was present at autopsy. The valve leaflets are
thickened: a congenital anomaly.
C. The right lung weighed
1000 g and the left, 900 g
(normal about 300-400g
each).
The right lung had a
fibrinous pleuritis.
After distension with
formalin and fixation, one
slice from the left lung
showed two yellowish
lesions.
QUESTION
Q11. What is the lesion cut surface of the lung?
Answer: The slice of lung shows two segmental pulmonary arteries
that are occluded by thrombus. Note the airway next to the vessel
near the center. No infarct or hemorrhage is present in the distal
parenchyma. These two thrombi probably came from the
pedunculated portions of the vegetations that were identified in the
echocardiogram.
D. A slice of the right
lower lobe showed
two lesions.
QUESTION
Q12. What are the lung lesions in image D?
Answer: The slice of lung in D shows two cavities with thin walls.
The larger abuts the pleura and may have been responsible for the
para-pneumonic effusion. Both cavities show small amounts of
residual necrotic lung, which is dark in the smaller cavity and pale in
the larger one. The cavitation is the result of pneumonia and
ischemia caused by septic thromboemboli as in C. Note the pleuritis
at the base (lower left).
QUESTION
Q13. How did the patient get the lesions in the lung?
The photos show typical consequences of right-sided infective
endocarditis: cavitated, pneumonic infarcts and pulmonary emboli
without infarction.
The liver (2200 g, normal 1500-1800 g) and spleen (320 g, normal
100 g) were enlarged. The kidneys were shrunken (R 75 g, L 92 g,
normal 150 g each) from the chronic membranoproliferative
glomerulonephritis. The brain was normal.
Histological changes at autopsy
The following sequence of photos shows the histological features.
A. The pulmonic vegetation is composed of a proteinaceous coagulum
that contains neutrophils and bacteria (dark blue). There was no
evidence of organization to indicate healing.
B. Section of the thrombus in one of the segmental arteries shown on the
previous page shows the same pattern as the vegetation, with PMNs and
bacteria. Note that the inflammation has spread into the vessel wall (blue
staining at arrows). The lack of parenchymal hemorrhage or infarction related
to this lesion, which is several days old, signifies that heart failure was absent.
Heart failure is a major factor that predisposes to infarction after pulmonary
embolism of a segmental artery.
C. Higher magnification of the same artery shown in B. The infected thrombus
(T) has caused transmural inflammation of the arterial wall (between 2
arrows). A portion of normal arterial wall (N) is also shown. Rupture of the
vessel can occur as a result of such an infective arteritis. When an infected
vessel dilates, it is called a mycotic aneurysm.
D. This vessel has an acute thrombus with some faint lines of Zahn
(platelet-fibrin columns (arrow)), transmural arterial inflammation, and
adjacent pneumonia with a necrotizing component (N) at the bottom left--the
beginning of a septic infarct.
E. A section from a cavitating lesion shows numerous, dark blue bacteria in
vessels and surrounding pneumonic consolidation of parenchyma that shows
coagulative necrosis with preservation of tissue outlines.
Other changes seen at autopsy [1]:
A slice of lung from the left upper lobe (A) and a histological section
from the same area (B) are shown.
QUESTION
Q14. Look at the slices carefully and describe the lesions.
A. Hint: The
abnormality is
related to colour.
B. Two
abnormalities are
present here. Hint:
The colour of the
macrophages is
important. What
about alveolar size?
Answer:
Black pigment is
present in a large
area in addition to
being present around
respiratory
bronchioles as small
spots. While the
latter are common in
cigarette smokers,
large areas of black
pigment are not.
Also, the air spaces
in the blackened
areas are slightly
enlarged with thin
walls: emphysema.
The histological
section shows large
numbers of alveolar
macrophages with
black pigment. A
stain for hemosiderin
pigment was
negative. Air spaces
are enlarged
compared to normal.
Diagnoses are:
1) excess black pigment caused by smoking crack cocaine
2) focal emphysema.
The photo shows a tube of dusky lavage fluid
from another crack smoker.
Pulmonary Complications of Smoking Crack Cocaine




Black sputum or lavage fluid
Barotrauma: pneumomediastinum, pneumothorax
Vascular injury: noncardiogenic pulmonary edema, pulmonary
hemorrhage, infarction
Parenchymal injury: acute eosinophilic pneumonia, organising
pneumonia sometimes with granulomas
Other changes seen at autopsy [2]:
A. This photo taken with polarized
light shows birefringent crystals
(bright spots) in the lung of the
patient. Numerous, scattered
crystals up to 40 µm long were
located mainly in the interstitium. A
few foreign-body giant cells were
present, but granulomas and scar
were absent.
B. Similar crystals were
found in macrophages in
the portal triads of the liver
shown here. Most were
less than 10 µm long, as
these crystals had
traversed the pulmonary
capillary bed. A
granulomatous response
was absent. Crystals were
also found in the spleen.
Crystals in intravenous drug users (IVDUs): Examination of the
lung sections of this patient with polarized light showed deposits of
foreign crystals. The crystals are deposited in arterioles and
capillaries but may erode through the vessel wall into the interstitium.
In some cases granulomas and fibrosis develop.
Effects of injection of oral medications: IVDUs sometimes inject
intravenously drugs that are intended for oral use. The tablets are
ground to a powder and dissolved in water before injection. Tablets,
including methadone, methamphetamine (speed), and
methylphenidate (Ritalin), contain fillers of talc, microcrystalline
cellulose, or starch.
These particles are trapped primarily in the pulmonary vasculature,
but some particles less than about 5 µm in diameter traverse the
capillary bed. As a result of systemic spread, the crystals may be
viewed in the microcirculation of the retina ophthalmoscopically. The
crystals do not interfere with visual acuity or other organ function.
Pulmonary effects may include fibrosis, emphysema, or
hypertension.
Diagnoses:






Infective endocarditis [IE] (methicillin resistant S. aureus),
pulmonic valve [congenitally malformed].
Infected emboli, lung.
Infective pulmonary arteritis.
Infected, cavitated infarcts in the lung.
Disseminated birefringent crystals in lungs, liver, spleen
(intravenous drug use).
Crack black lung.
Clinical Comment:
Review of the trans-oesophageal echocardiogram from 05/05 (about
2 months before death) showed a small (0.7 cm) vegetation on an
abnormally thickened pulmonic valve (PV).
The diagnosis was probably dismissed because the PV is almost
never involved in infective endocarditis (IE).
The onset of IE probably coincided with the development of the
septic arthritis.
Death was ascribed to respiratory failure from septic emboli, infarcts,
and pneumonia.
Pathology discussion of case
Infective Endocarditis [IE]
Introduction: Infective endocarditis (IE) has a varying epidemiology
depending on individual risk factors present in a given population.
The frequency of various types of congenital, acquired, and
degenerative cardiac valve diseases, intravenous drug use, diabetes,
and malignancy contributes to the incidence of disease in a
population. Other predisposing factors include localized chronic
infections, alcoholism, splenectomy, and immunosuppression [1].
Further, a high autopsy rate is important for diagnosis of cases that
are missed clinically [2,3]. Outcome of IE depends on the particular
organism involved, as well as on early diagnosis and treatment [1]. A
uniformly fatal disease in the pre-antibiotic era, it has changed to one
with a mortality rate of around 40% when caused by S aureus [1], but
there are wide variations in mortality rates depending on valve(s) and
organism involved. Complications are associated with considerable
morbidity. Not all cases are community-acquired as nosocomial IE
may occur in the setting of intravascular or intracardiac catheters
[1,2]. It is still useful to separate the clinical syndromes of acute and
subacute endocarditis on the basis of predisposing cardiac disease,
virulence of the organism, and severity of the symptoms, despite
some overlap [1]. Host factors and organisms in acute endocarditis
have been discussed recently in two reviews: one summarizes the
literature [1], and the other describes the disease in a Swedish city of
428,000 from 1984 to 1988 [3]. Here, discussion will focus first on the
acute disease, in general, and then on aspects of the disease in
intravenous drug users (IVDUs).
Clinical features: Ordinarily, the disease presents with high fever,
chills, and malaise. The classic new or changing murmur, however,
can be absent in up to a third of cases. There may be left ventricular
failure. Extra-cardiac features of left-sided valve involvement include
stroke, acute mental status change, meningitis, arthralgia,
osteomyelitis, septic arthritis, splenic infarct, renal abscess, and
Janeway lesions (non-tender red spots on the palms or soles). Extracardiac manifestations of right-sided valve involvement include
dyspnea, cough, pleurisy, and hemoptysis caused by septic infarcts,
pneumonia, or empyema. Laboratory findings include blood cultures
positive for virulent organisms, leukocytosis, hematuria, pyuria, and
increased sedimentation rate [1]. Pulmonary radiographic findings
with right-sided endocarditis include multiple rounded opacities,
cavitating masses, and pleural effusions [1].
Diagnosis: Criteria based on clinical findings alone [4] have recently
been expanded to incorporate echocardiographic features (table),
which have increased the sensitivity of making a diagnosis [5].
Clinically, exclusion of a non-cardiac source of bacteremia, persistent
bacteremia with typical organisms, fever >38°, cardiac murmur,
history of cardiac procedure or device, consistent septic emboli, and
otherwise unexplained peripheral manifestations suggest the
diagnosis [1]. Transesophageal echocardiography (TEE) that is
performed by an experienced echocardiographer, with or without a
preceding transthoracic echocardiogram (TTE), can diagnose a
vegetation or myocardial abscess in over 90% of cases [1,6].
Simultaneous Doppler studies demonstrate abnormal flow patterns of
fistulas and valve perforations. Imaging of the PV can be difficult in
the transverse plane with TEE, but use of a biplane probe to show a
longitudinal view of the outflow tract improves the diagnostic
usefulness [7]. A recent report found that the diagnosis of IE relied on
clinical findings in only 7% of 103 patients with S aureus bacteremia.
In contrast, 26% had findings of IE by TEE [2]. For neurologic
findings, head CT ± MR to detect infarcts or abscesses, and cerebral
arteriography to detect mycotic aneurysms are further diagnostic
adjuncts [1].
Table 1: Duke Criteria for IE [5]
Major criteria: a) positive blood cultures of a designated number and
with an appropriate type of organism, b) positive echocardiogram
with specific features
Minor criteria: a) predisposition: cardiac abnormality or IVDU, b)
fever, c) vascular manifestations, d) immunologic features, e) other
microbiologic or echocardiographic evidence
Definite diagnosis rests on 2 major, 1 major and 3 minor, or 5 minor
criteria.
Cases not completely rejected are diagnosed as possible IE and
treated on the basis of clinical judgment.
Differential diagnosis: Infected hemodialysis shunts, suppurative
thrombophlebitis, septic arthritis, and skin or other abscesses can
cause bacteremia and pulmonary lesions without endocarditis.
Further, patients with IVDU may not have classic findings of IE, as in
the patient presented here [1].
Histological changes: In general, vegetations of acute IE occur on
normal valves and are large and friable, whereas those of subacute
IE occur on fibrotic valves and tend to be small. Factors predisposing
to subacute IE are the sterile platelet-fibrin thrombi that develop
during the remodeling of previously-damaged valves. Adherence of
bacteria in the presence of agglutinating antibody initiates the
vegetation, which in both types of IE is composed of a proteinaceous
coagulum with embedded inflammatory cells and bacteria. With time,
organization and calcification may occur, especially in subacute
disease. The vegetations may cause perforation of valve leaflets or
rupture of chordae tendineae. Spread of infection to the myocardium
can lead to abscesses or fistulas between chambers or to the
pericardium. Systemic emboli most frequently involve the brain,
spleen, coronary arteries, and kidneys. Besides producing infarcts or
abscesses, mycotic aneurysms may develop and rupture to produce
hemorrhage. Septic emboli from the right heart to the lungs may be
accompanied by hemorrhages or infarcts that usually become
infected and may then cavitate [1].
Treatment: Antibiotic therapy may be curative. When antibiotics fail,
indications for surgical therapy include severe congestive heart
failure, persistent infection, embolic complications, myocardial
abscess, and valve perforation or dehiscence of a prosthetic valve
[1].
Outcome: The mortality rate for IE is dependent on many factors as
indicated above. In one small study, factors predicting death included
systemic embolism, paravalvar abscess, S aureus endocarditis, and
antibiotic treatment alone. Risk of embolization increased with the
total length of the vegetations measured by TEE [8]. Five-year
survival after valve replacement for IE is 47 to 71% in the non-IVDU
population [1].
IE in IVDUs: A report from Cook County Hospital, Chicago,
describes the disease in 125 episodes of native valvar IE in IVDUs
during a 4-year period from 1988 to 1991 [9]. These cases accounted
for 94% of all IE cases seen at that hospital during that time. Salient
features are tabulated below.
Table 2: Summary of Characteristics of IVDUs with IE [9]
Gender
Age, mean
Other
predisposing
factors
M:F 2:1
37 years (range 23-59)
Past IE (22%), rheumatic heart disease (2%)
Signs
Fever >37.8° C (83%), cardiac murmur (70%),
anemia (38%), hepatomegaly (30%),
splenomegaly (11%), microhematuria (47%)
HIV+/HIV/unknown
25%/36%/39%
Organisms
S aureus
Streptococcus
S aureus (67%, of which 15% were methicillin
resistant),
Streptococcus (26%, of which 63% were S
viridans)
Organisms by valve affected
TV 60%*, MV 20%, AV 12%, multiple valves
16%
TV 22%, MV 56%*, AV 25%, multiple valves
12% *Significantly different from other valves.
Any right-sided
47%
valve involvement
Any left-sided
58% (right & left-sided difference not significant)
valve involvement
Treatment and
82% medical with 9% inhospital deaths
outcome
18% medical + surgical with 9% inhospital
deaths
About 70% had a major cardiovascular
complication
Outcome by valve involved (extremes only)
Tricuspid valve
16% had surgery or died without surgery
63% had surgery or died without surgery (P =
Aortic valve
0.02)
Congestive heart failure (19%), stroke (11%),
Non-fatal
other systemic emboli (16%), septic pulmonary
complications
emboli (66% of those with right-sided
vegetations)
HIV infection and IVDU: Another study contrasted the site of
infection in 102 IVDUs in Cook County with (45) and without (57) HIV
infection (diagram). The differences between HIV-positive and
negative patients for location of the endocarditis were significant. S
aureus was the most common pathogen in both groups [10]. S
aureus was more likely to affect the TV, and streptococci were more
likely to affect the MV. IE of the PV is vanishingly rare. Review of
valves involved by IE in 449 IVDUs reported since 1970 found that
the pulmonic valve was involved in only 1 case [9].
Pathogenesis of IE in IVDUs: The source of S aureus may be the
skin, nose, or throat of the patient, as bacteriophage types from these
sites have been shown to be similar to those in isolates from the
blood. Other sources of infection in the addict include skin
abscesses, osteomyelitis, and septic arthritis [11]. Virulent organisms
can infect normal valves. In contrast, in our case, the pathogenesis of
disease is probably that proposed for patients with subacute
endocarditis: platelet-fibrin thrombi that develop during lifelong
remodeling of a congenitally deformed valve trap bacteria when there
is a high titer of agglutinating antibody [9].
Outcome: An inhospital death rate of 9% for 125 episodes of IE is
given in Table 2. A retrospective study compared the outcome of IE
in 45 HIV-positive and 57 HIV-negative IVDUs in Cook County
hospitals from 1987 to 1992. Only two of the HIV-positive patients
were receiving anti-retroviral therapy, and only 1 was taking
prophylaxis for pneumocystis. Age and gender were similar in both
groups. S. aureus was the most common pathogen. HIV-negative
patients had echocardiographically visible vegetations more
frequently than HIV-positive patients (77% vs 56%, respectively), and
right-sided valves were involved more frequently in HIV-positive
patients, and left-sided valves more frequently in HIV-negative ones
(see diagram above). Mortality in the hospital was similar in both
groups (8.8% for HIV-negative and 13.3% for HIV-positive), but HIVnegative patients died only if left-sided valves were involved whereas
the mortality in HIV-positive patients did not depend on the valve
infected. The mortality rate for HIV-positive patients increased with
decreasing CD4 count. Of those with CD4 counts <200/µl, 56% died;
no deaths occurred if the count was >500/µl [10]. For those who
underwent surgery, non-compliance with anticoagulation and
continued IVDU contributed to a high out of hospital mortality [9].
References
1. Cunha B, Gill M, Lazar J. Acute infective endocarditis. Diagnostic
and therapeutic approach. Infect Dis Clin N Am 1996; 10:811-834.
2. Fowler Jr V, Li J, Corey G, Boley J, Marr K, Gopal A, Kong L, et al.
Role of echocardiography in evaluation of patients with
Staphylococcus aureus bacteremia: experience in 103 patients. J Am
Coll Cardiol 1997; 30:1072-1078.
3. Hogevik H, Olaison L, Andersson R, Lindberg J, Alestig K.
Epidemiologic aspects of infective endocarditis in an urban
population. A 5-year prospective study. Medicine 1995; 74:324-339.
4. Von Reyn C, Levy B, Arbeit R, Friedland G, Crumpacker C.
Infective endocarditis: an analysis based on strict case definitions.
Ann Intern Med 1981; 94:505-518.
5. Durack D, Lukes A, Bright D. New criteria for diagnosis of infective
endocarditis: utilization of specific echocardiographic findings. Am J
Med 1994; 96:200-209.
6. Daniel W, Mügge A. Transesophageal echocardiography. N Engl J
Med 1995; 332:1268-1279.
7. Winslow T, Foster E, Adams J, Schiller N. Pulmonary valve
endocarditis: improved diagnosis with biplane transesophageal
echocardiography. J Am Soc Echocardiogr 1992; 5:206-210.
8. Lancellotti P, Galiuto L, Albert A, Soyeur D, Piérard L. Relative
value of clinical and transesophageal echocardiographic variables for
risk stratification in patients with infective endocarditis. Clin Cardiol
1998; 21:572-578.
9. Mathew J, Addai T, Anand A, Morrobel A, Maheshwari P, Freels S.
Clinical features, site of involvement, bacteriologic findings, and
outcome of infective endocarditis in intravenous drug users. Arch
Intern Med 1995; 155:1641-1648.
10. Pulvirenti J, Kerns E, Benson C, Lisowski J, Demarais P,
Weinstein R. Infective endocarditis in injection drug users:
importance of human immunodeficiency virus serostatus and degree
of immunosuppression. Clin Infect Dis 1996; 22:40-45.
11. Ang-Fonte G, Rozboril M, Thompson G. Changes in
nongonococcal septic arthritis: drug abuse and methicillin-resistant
Staphylococcus aureus. Arthritis Rheum 1985; 28:210-213.
end
Congenital Abnormalities of the Pulmonic Valve
Semilunar valves: The normal semilunar valve has 3 equal-sized cusps or
leaflets and 3 commissures between leaflets (A). Congenital abnormalities
of the pulmonic valve are rare--21 in 3600 (0.58%) consecutive autopsies in
one series--and include pulmonic stenosis and bicuspid and quadricuspid
pulmonic valves [1]. Any developmental deformity predisposes the valve to
remodeling because of abnormal hemodynamics of valve closure. Continued
erosion and repair produce thickening and predispose to infection just as in
acquired valvar disease. In a study of 360 congenitally malformed semilunar
valves, 208 involved the pulmonic, and 108 involved the aortic valve
(1.9:1). Age range was from 0 to 77 y with a mean of 8 y, and 90% were
under age 16. Males outnumbered females 153:120 (1.3:1). None of the
valves, however, resembled that seen in our patient [2].
A. Normal pulmonic valve. Note the
thin, translucent valve cusps. The
commissural junction of the cusps is
normal.
Congenital lesion in this patient: A deformity similar to that found in our
patient was described in inbred Syrian adult hamsters with a high incidence
of abnormalities of the pulmonic valve. Of 206 abnormal valves, 21 showed
a spectrum from tricuspid to quadricuspid: 9 were quadricuspid, 7 were
tricuspid with a raphe (ridge) in the right pulmonary sinus (space behind the
cusp) and fusion of the dorsal commissure (opposite the aortic valve), and 5
were tricuspid with a raphe in the right sinus. This last anomaly corresponds
to that found in our patient. He had 3 normally-formed commissures and 3
equally proportioned cusps, but behind the right cusp was a shallow raphe
that indicated a partially formed 4th commissure (B). This condition is
thought to result from partial division of the right valve cushion very early
in its development. The authors postulate that the abnormalities of the
semilunar valves may be mediated during embryogenesis by cells of the
neural crest that act separately on the aortic and pulmonic valves [3].
B. Although the vegetation (V) on the anterior
cusp caused partial obliteration of the
commissure between it and the right cusp, all
commissures appeared to have been normally
formed, and cusps were of the same size. A
shallow raphe (R) that originated opposite the
aortic commissure (diagram) was present at the
base of the right cusp, and the commissure
between right and left cusps (arrow), which
should have been opposite the aortic
commissure, was shifted slightly to the left. All
the cusps were thickened. A vegetation (not
shown) was also present on the left cusp at
autopsy.
C. This diagram shows the aortic (AV) and
pulmonic valve (PV) cusps and their
commissures in this patient. The raphe in the
right sinus originated opposite the commissure
of the aortic valve, and the commissure between
the right and left cusps was shifted to the left. R
= right cusp, L = left cusp, A = anterior cusp
References
1. Koletsky S. Congenital bicuspid pulmonary valves. Arch Pathol 1941;
31:338-353.
2. Moore G, Hutchins G, Brito J, Kang H. Congenital malformations of the
semilunar valves. Hum Pathol 1980; 11:367-372.
3.Fernández B, Fernández M, Durán A, López D, Martire A, Sans-Coma V.
Anatomy and formation of congenital bicuspid and quadricuspid pulmonary
valves in Syrian hamsters. Anat Rec 1998; 250:70-79.