according to the current who classification , intravascular large b - cell lymphoma ( ivl ) is a rare type of non - hodgkin 's lymphoma characterized by the selective growth of tumor cells within the lumens of the small vessels in various organs , including the kidney [ 1 , 2 ] . in 2003 , tornroth et al .  
reviewed renal involvement by ivl based upon previous reports and their own cases and concluded that this disease can be divided into an intraglomerular type and a type with tubulointerstitial invasion .
they stated that the latter type features diffuse invasion of lymphoma cells into the tubulointerstitial region . in 2007 , sawa et al .  
reported the first case of tubulointerstitial ivl limited to the peritubular capillaries . in 2009 , kameoka et al .  
in fact , the majority of patients who have been reported with renal involvement by ivl also had extrarenal lesions in addition to renal ones .
we encountered a 65-year - old japanese woman with kidney - limited ivl localized to the glomerular capillaries in whom c - reactive protein ( crp ) was negative . here , we review the relation between kidney - limited ivl and crp based on this case and previous reports .
a 65-year - old japanese woman was admitted to our hospital for the evaluation of rapidly progressive renal dysfunction . at the age of 60 years ( april 2000 )
subsequently , proteinuria ( 41 mg / dl ) was noted , and serum creatinine ( cre ) was 0.94 mg / dl . on september 3 , 2005 , edema of the bilateral lower extremities was noted with exacerbation of hypertension ( 200/110 mm hg ) .
her height was 154 cm , her weight was 48.2 kg , her blood pressure was 152/92 mm hg , and her temperature was 35.9c .
urea nitrogen was 41 mg / dl , and cre was 2.7 mg / dl .
crp was 0.1 mg / dl , and the erythrocyte sedimentation rate was 53 mm / h .
soluble interleukin-2 receptor was elevated to 1,680 u / ml ( normal range : 250590 ) .
light microscopy of a specimen containing 12 glomeruli revealed global sclerosis in 2 . there was mild fibrosis and atrophy , as well as very slight cellular infiltration , in the tubulointerstitial region ( fig .
2b ) , and the glomerular capillaries were filled with large atypical cells that had atypical nucleoi ( fig . 2c ) . there was no increase in the mesangial matrix or mesangial cell proliferation .
immunohistochemical staining detected atypical large lymphoid cells in the glomerular capillaries that were positive for cd20 ( fig .
lymphocytes in the tubulointerstitium were positive for cd3 , but negative for cd20 and cd79a .
electron microscopy revealed numerous atypical cells with large nuclei , large nucleoli , masses of chromatin in the outer zones of the nuclei , and an abundance of endoplasmic reticulum ( fig .
based on these findings , kidney - limited ivl localized to the glomerular capillaries was diagnosed .
treatment with chop regimen , including cyclophosphamide of 1,000 mg ( 750 mg / m ) , hydroxyl doxorubicin of 70 mg ( 50 mg / m ) , and oncovin ( vincristine ) of 2 mg ( 1.4 mg / m ) intravenously for 1 day and prednisolone of 100 mg orally daily for 5 days was started .
this symptom was considered due to motor neurological dysfunction , probably related to an overdosage of vincristine .
thus , at the second cycle , this drug was switched to vindesine of 3 mg , and rituximab of 600 mg was added ( as r - chop therapy ) , and a total of 6 cycles were performed at 4-week intervals .
her serum creatinine decreased from 3.2 to 1.4 mg / dl , and urinary protein became negative immediately after the end of the r - chop therapy .
two months after completing 6 courses of therapy , relapse occurred with an increase in lactate dehydrogenase .
she then received 3 courses of rituximab of 600 mg , cyclophosphamide of 850 mg , cytosine arabinoside of 1,400 mg for 2 days , etoposide of 70 mg for 3 days , and dexamethasone of 40 mg for 3 days ( r - chase therapy ) as salvage chemotherapy , and complete remission was achieved .
after 108 months , she is doing well with a cre of 1.21 mg / dl , daily urinary protein excretion of 0.21 g , crp of 0.01 mg / dl , and lactate dehydrogenase of 197 iu / l .
ivl was first reported in 1959 by pfleger and tappeiner   as  angioendotheliomatosis proliferans systemisata. according to the latest who classification , ivl is a rare type of extranodal diffuse large b - cell lymphoma .
patients with ivl usually have no lymphadenopathy , and tumor cells involve the small vessels of many organs , such as the bone marrow , central nervous system , skin , lungs , liver , kidneys , and intestinal tract .
ivl is very aggressive , and the prognosis is usually extremely poor , but chemotherapy including a chimeric anti - cd20 monoclonal antibody ( most commonly rituximab ) has been reported to achieve a relatively good response , and autologous stem cell transplantation can also lead to good outcomes . the serum level of crp is known to be a nonspecific simple test that may become positive for numerous inflammatory conditions . however , this test can be a useful prognostic marker for non - hodgkin 's lymphoma and hodgkin 's lymphoma associated with interleukin-6 overproduction .
all 5 patients showed elevation of crp . among them , 2 patients had bone marrow involvement , and 1 patient showed skin lesions .
renal biopsy showed the intraglomerular type in 1 patient , but autopsy demonstrated minute lymphoma aggregates in the peritubular capillaries as well as intraglomerular tumor cells .
crp was 16.2 mg / dl , and only occasional interstitial tumor cells were detected .
subsequently , involvement of the lymph nodes , liver , spleen , lungs , and bone marrow became apparent in this patient .
crp was normal at 0.02 mg / dl , and extrarenal involvement was not detected . in conclusion , we managed a patient with intraglomerular ivl limited to the intraglomerular capillaries , without extraglomerular or extrarenal involvement .
however , elevation of crp may occur in patients who have renal ivl with interstitial involvement or extrarenal lesions . because crp is a systemic inflammatory marker that indicates overproduction of interleukin-6 , elevation of crp
may be involved in the process by which the disease progresses from the intraglomerular capillaries to the systemic vessels .
 a 65-year - old woman was admitted to our hospital for the evaluation of rapidly progressive renal dysfunction with serum creatinine of 2.7 mg / dl and urinary protein of 1.5 g daily . 
 c - reactive protein ( crp ) was 0.1 mg / dl . 
 kidney - limited intravascular large b - cell lymphoma ( ivl ) localized to the glomerular capillaries was diagnosed because the intraglomerular cells were positive for cd20 and cd79a , while there was no positivity in the extraglomerular kidney and extrarenal organs . 
 treatment with rituximab , cyclophosphamide , hydroxydaunomycin , vincristine , and prednisolone was started , and the patient has since been doing well . when ivl is limited to the intraglomerular capillaries , crp may not be elevated . 
Introduction
Case Report
Renal Biopsy Findings
Clinical Course
Discussion
Disclosure Statement