A high index of clinical suspicion must be maintained for febrile presentations in the asplenic
patient or one with a chronic disease that can produce a dysfunctional spleen. Patients may
present with nonspecific symptoms like, low-grade fever, chills, rigors, pharyngitis, muscle
aches, and vomiting and diarrhea that might have been present for one to two days prior to
clinical deterioration (10). In the setting of known asplenia or splenic dysfunction any febrile
illness with or without focal symptoms must be suspected to be postsplenectomy sepsis.
Usually no clinically demonstrable site of infection is found in adults. In children younger than
five years, however focal infections, particularly meningitis are more prominent. Following the
prodrome, deterioration can be very rapid, with progression to hypotension, DIC, diffuse
purpura, respiratory distress, and coma can occur in hours rather than in days. Peripheral
gangrene requiring amputations has been reported in survivors. Adrenal hemorrhage has
frequently been described in cases that come to autopsy. Bacteria can be seen on microscopic
examination of peripheral blood and in multiple organ systems in autopsied cases (40–44).
Other sequelae include, deafness associated with meningitis and mastoid osteomyelitis, and
aortic insufficiency following endocarditis (45,46).
Diagnosis and Management
The management of OPSIs includes initial aggressive management of the acute illness followed
by combination of immunization, antibiotic prophylaxis, and patient education. Diagnostic
workup should never delay the presumptive antibiotic therapy. Bacteria can be visualized on
Gram stain or Wright stain of the peripheral blood Buffy coat, and if seen on peripheral blood
smear it suggests a quantitative bacteremia of> 10
6
/mL, which is four logs or greater than that
of usual bacteremia. Because of this degree of bacteremia, blood cultures are positive in 12 to
24 hours. Any bullous lesions should be aspirated for Gram stain and culture. A CSF
examination may be needed based on clinical symptoms, particularly in children because of
the high incidence of meningococcal meningitis with sepsis. Standard lab tests like complete
blood count, serum chemistries, and appropriate radiologic studies should be done. In a
patient who is postoperative day 5 after splenectomy for trauma, WBC greater than 15 103 /
microl and platelet to WBC ratio less than 20 are reliable marker of infection (47). Further tests,
including the peripheral smear for malaria or babesiosis, should be guided by the patient’s
history. Ascitic and pleural fluid should be examined, if indicated. Furthermore, Howell–Jolly
bodies or other evidence of hyposplenism should be sought, especially in an individual with a
history of an illness predisposing to hyposplenism.
Antimicrobial Therapy
Currently there is no proof that early treatment will prevent incipient bacteremia from
progressing to full-blown OPSI. However, the literature does support that an aggressive
approach improves survival (48). Despite the absence of any controlled studies, self-
administration of an antibiotic at first sign of suspicious illness in the asplenic or hyposplenic
person is advised, this should be specially instituted if delivery of medical care is not
immediately available. In an outpatient setting, a patient suspected to have postsplenectomy
sepsis should receive an appropriate broad-spectrum antimicrobial such as ceftriaxone
parenterally prior to hospital transfer, whether or not blood cultures are obtained. Local
resistance patterns should be taken into account when selecting an initial presumptive
regimen, with consideration of antibiotic, such as ceftriaxone and cefotaxime, which are active
against penicillin-resistant pneumococci, as well as beta-lactamase producers such as
H. influenzaeandC. canimorsus. Some penicillin-resistant pneumococcal isolates are also
resistant or only intermediately susceptible to cephalosporins. If such resistance is suspected,
the use of vancomycin combined with gram-negative antibiotic coverage for organisms such as
meningococcus must be considered. High-level penicillin-resistant pneumococci will definitely
require vancomycin with or without rifampin. Other choices include an anti-pneumococcal
quinolone, such as levofloxacin, amoxicillin/clavulanic acid, trimethoprim/sulfamethoxazole,
or a newer macrolide (clarithromycin, azithromycin). Levofloxacin has activity against
penicillin-resistantS. pneumoniae, as well as gram-negative organisms includingH. influenzae,
N. meningitidis, andC. canimorsus. Amoxicillin/clavulanic acid has activity against beta-
lactamase–producing H. influenzae and C. canimorsus but not against penicillin-resistant
Severe Infections in Asplenic Patients in Critical Care 353