a male patient ( 165 cm in height , 61 kg and 62-year - old ) was transferred to our hospital because of the chief complaint of back pain .
the back pain had developed approximately 2 months previously without specific trauma , and the area around the left buttock was most painful .
the pain worsened while standing up and turning around , and it was improved while lying down .
there were no findings of radicular pain , costovertebral tenderness or spinal tenderness , and the muscle strength of both low extremities was grade 5 , which was normal .
the patient was hospitalized for the evaluation of renal function and treatments because of the elevated cpr .
the patient had been hospitalized at the a hospital for back pain 2 months previously and bulging discs ( l3/4 , l4/5 ) were detected by lumbar magnetic resonance imaging ( fig .
1 ) . hypoxia and fever had developed during the hospitalization ; atypical pneumonia was suspected and he had received treatment .
nonetheless , the pain and other symptoms had not improved and so he was transferred to the b hospital .
he was diagnosed with possible scrub typhus , doxycycline was prescribed and the fever subsided and he was discharged after one week . at that hospital , he was diagnosed as suffering from chronic renal failure caused by glomerulonephritis .
the back pain was diagnosed as l4 - 5 facet pain and so a lumbar median branch block was performed . after he initially improved 10 - 20% for 3 days , the back pain recurred and persisted until the time of transfer to our hospital . for his past medical history ,
the vital signs of the patient at the time of transfer were a blood pressure of 115/90 mmhg , a pulse rate of 68 beats / min , a respiratory rate of 18 breaths / min and the body temperature was 36.4. the blood test of the patient showed that the number of leucocytes and the crp level were normal , and the esr was elevated to 49 mm / hr . first , a diagnostic epidural block was performed using a c letter type image intensifier ( oec 9800 plus , ge medical system , usa ) .
epidural block in the left l 4 - 5 interlaminar space was performed and 10cc of 0.125% ropivacaine and 20 mg tamceton were injected . the next day after the epidural block ,
since the symptoms of the patient and the findings of the previously performed lumbar mri did not concur , magnetic resonance imaging was performed again after 2 days .
a paravertebral abscess and findings of infective spondylitis were detected on the lumbar magnetic resonance imaging ( fig .
an aspiration culture test was performed for the abscess and salmonella group d was cultured .
the patient was finally diagnosed with salmonella spondylitis , and ceftriaxone was administered according to the results of the antibiotic sensitivity test .
the symptoms of the patient and the results of the hs - crp then showed a tendency to improve . during the administration of antibiotics , there was persistent deterioration of the kidney function and uremia symptoms developed , and so hemodialysis was performed . despite the administration of appropriate antibiotics , the patient showed intermittent fever and a trend for increased pain .
mri follow - up was performed 4 weeks after the administration of antibiotics , and the abscess was shown to have increased in size .
afterward , at that hospital , the patient was treated with a combination of ciprofloxacin and ceftriaxone without surgery for 4 weeks , and then he was again transferred to our hospital because it is located in his hometown .
thirteen weeks after the administration of antibiotics , his back pain was much improved ( vnrs : 1/10 ) and he was able to walk . on the blood test , the hs - crp level was 0.34 mg / dl .
on the lumbar mri , the abscess showed improvement and so the antibiotics were terminated . the patient is currently under follow - up observation at our outpatient clinic ( fig .
when a patient is transferred from another department for pain , the patient is examined during the mid course of disease , and so it is difficult to understand the overall problems of the patient . for our patient ,
nonetheless , his fever was diagnosed as possible atypical pneumonia and scrub typhus . after taking various antibiotics and anti - inflammatory agents ,
the blood culture test was negative and so the diagnosis of back pain was delayed . at the time of transfer , his back pain was severe , but any fever was not detected . on the blood test results ,
the leukocyte count and hs - crp level showed normal findings and this made it difficult to suspect infection .
furthermore , bulging discs were detected on the lumbar mri that was previously performed and a diagnostic epidural block was then done .
an epidural block can suppress selective pain pathways ; hence , it is frequently used for the diagnosis and treatment of acute and chronic pain .
however , the symptoms were not improved after the lumbar epidural block ; lumbar mri was performed again and infective spondylitis as well as a psoas abscess were shown .
an aspiration test was performed on the paravertebral abscess , salmonella group d was cultured , and the man was diagnosed with salmonella spondylitis .
it has been reported that salmonella bacteria is the causative bacteria in less than 1% of the cases of hematogenous spondylitis and it rarely causes spondylitis in humans .
it develops in the spine in the order of the lumbar vertebras and the thoracic vertebras .
the risk factors are sickle cell anemia , hemoglobinopathies , underlying bone diseases , chronic liver diseases , connective tissue diseases , malignant tumors , the use of steroids , old age , diabetes , etc . .
it has been reported that in sickle cell anemia patients , more than 70% of the spondylitis is caused by salmonella , and it has rarely reported in patients without sickle cell anemia [ 5 - 7 ] . in patients with normal immune function ,
the major symptoms of salmonella spondylitis are back pain ( 100% ) , fever ( 75% ) , elevation of the esr and elevated c - reactive protein levels ( crp ) .
an elevation of the leukocyte count has not been consistently reported and the blood culture was positive in approximately 75% of patients [ 5 - 7 ] .
nonetheless , the diagnosis of fever varied and several antibiotics were administered resulting in the alteration of the typical findings , and so the diagnosis became difficult . in patients with salmonellosis , the symptomatic period has widely varied from 10 days to 12 years , and it is on average 8 weeks . it has been reported that after the first infection with salmonella , the infection may remain as the latent form for a long time , and when the function of reticular endothelial cells is deteriorated , it may become activated and consequently , it may secondarily induce metastatic infection in the bone several months or several years after acute salmonellosis .
low signal intensity on t1wi and high signal intensity on t2wi were shown as the typical pattern of mri . nevertheless , negative mri findings during the initial period of disease have been reported .
hence , for cases that infective spondylitis is suspected clinically according to the blood tests , it is recommended to perform mri at a minimum interval of 2 weeks .
our patient also did not show special findings , except bulging discs , on the lumbar mri during the initial period , and spondylitis was shown on the mri performed again after 2 months .
we can speculate that the incubation period for salmonella is long , and so our patient was shown to be negative on the mri taken during the early symptomatic period .
so , if the symptoms of a patient persist or are vague , then a re - work up process may be required .
salmonella spondylitis can be diagnosed by culture tests of blood , feces , bone , abscess , etc . .
fifty - two percent of the reported cases were diagnosed by tissue culture of bone or abscess , 48% of the cases were diagnosed by blood culture and the fecal or urine culture tests were shown to be positive in 36% and 23% of the cases , respectively . for our case ,
the blood culture test was negative because the patient took antibiotics for an unknown fever .
however , salmonella was identified on the abscess culture test and so the patient was diagnosed . in regard to complications , paravertebral abscess is present in 39% of the cases , epidural abscess is present in 4% , abscess in the spleen is present in 2% and infective aortic aneurysm is present in 28% .
salmonella is a common causative bacteria for inducing infectious aortic aneurysm and it induces spondylitis at the adjacent spine .
when the aorta or spine is infected first , the septic embolus is lodged in the vasa vasorum and the infection travels along the outside of the adjacent blood vessels to the adjacent organs ; infectious aortic aneurysm and spondylitis occur simultaneously in many cases . in our patient 's case ,
surgery was performed for a ruptured aortic aneurysm 10 months prior to the diagnosis of salmonella spondylitis .
considering the long incubation period of salmonella , the ruptured aortic aneurysm may have been due to salmonella .
in addition , pneumonia and subacute renal failure may be complications of salmonella bacteremia . spondylitis accompanied with abscess in the psoas muscle is a common complication of salmonella bacteremia , which was also observed in our case .
salmonella is classified to subgroups according to the surface antigens , and particularly depending on the o antigen , it is classified into the a to e group . in the korean reports ,
salmonella spondylitis was primarily caused by the d group , and this was also true for our patient .
the primary treatment is appropriate antibiotics based on the results of the culture test and also appropriate drainage of any abscess in the adjacent organs .
surgical treatments are required for the cases with osseous instability , neurological deficits , clinical unresponsiveness to antibiotics , refractory infection and the failure of biopsy to provide a firm diagnosis .
the length of the treatment period is still controversial , but more than a minimum of 4 weeks is required .
improvement of the clinical symptoms and reduction of the c - reactive protein values are the major indexes of the treatment response .
if the infection is not improved after 4 weeks of treatment , then an epidural abscess should be suspected , and repeat imaging is useful for the patients who improve without drainage treatment despite the presence of a big abscess , and termination of antibiotic treatments should then be considered .
salmonella spondylitis responds well to the appropriate antibiotics and it is completely cured in 76% of the patients . on the other hand , in approximately 17% , the condition appears to progress to chronic spondylitis .
the prognosis has been shown to be good for young patients who are without preceding factors .
this patient was also a patient without preceding factors and he improved with only antibiotic treatment . in conclusion ,
our case was a patient with back pain that persisted for longer than 2 months .
the lumbar mri was negative in the initial period and since antibiotics were administered for fever , the diagnosis of salmonella spondylitis was delayed . assessing the comprehensive disease history and performing a diagnostic nerve block are necessary for the patients who are transferred from another department .
if the treatment effects are atypical , then more comprehensive tests are required for making the diagnosis .
 salmonella spondylitis is a rare illness , and it generally occurs in patients who have already had sickle cell anemia , and it is even rarer in patients who are without sickle cell anemia . 
 a 61-year - old male patient was hospitalized for the evaluation of his renal function and then treatment was started for his back pain . 
 his back pain had developed about 2 months previously without any specific trauma . 
 only a bulging disc was detected on the initial lumbar mri . 
 regarding his fever , it was diagnosed as possible atypical pneumonia , scrub typhus , etc . , and 
 multiple antibiotic therapy was administered . at the time of transfer , 
 the leucocytes and hs - crp were normal and the esr was elevated . 
 a diagnostic epidural block was performed for his back pain , but his symptoms were not improved . 
 lumbar mri was performed again and it showed findings of infective spondylitis . 
 salmonella d was identified on the abscess culture and so he was diagnosed as suffering from salmonella spondylitis . 
 after antibiotic treatment , his back pain was improved and the patient was able to walk . 
Case Report
Discussion