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IDNEY BIOPSY TEACHING CASE

Chronic Renal Failure and Abnormal Tubular Cells in 2 Siblings

Michele Rossini, MD, Susan Coventry, MD, Don R. Duff, MD, and Agnes B. Fogo, MD

NDEX WORDS: Karyomegaly; nephropathy; proteinuria; ochratoxin; HLA haplotype association.

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HRONIC TUBULOINTERSTITIAL ne-phritis is a diagnosis usually made of a

onspecific lesion, often with undetermined un-erlying cause, after specific crystals, casts, viralnfections, or drug reactions are excluded. Weeport on unique tubular nuclear changes in renaliopsy specimens of 2 brothers that shed light onhe nature of their chronic tubulointerstitial dis-ase.

CASE REPORTS

ase 1Clinical history. A 41-year-old white man presented

ith diaphoresis, weakness, and nausea. A workup for an-ina was performed, and he was noted to have underlyingenal insufficiency of unknown cause, with a serum creati-ine level of 2.0 mg/dL (177 �mol/L). The patient had noistory of hypertension or diabetes mellitus. He had a historyf rare cigarette use, with no significant alcohol consump-ion. His family history indicated his brother had chronicenal failure of unknown cause.

Findings from the remaining review of systems and physi-al examination were negative. Pertinent laboratory valuesncluded a blood urea nitrogen level of 23 mg/dL (8.2mol/L), creatinine clearance of 59 mL/min (0.98 mL/s),

nd 24-hour urinary protein excretion of 285 mg. Serumrotein electrophoresis, renal ultrasound, and renal scansere normal.A percutaneous renal biopsy was performed in June 2000.Renal biopsy. The renal biopsy specimen contained cor-

ical tissue with 37 glomeruli, 24 of which were hyalinized.n light microscopy, there was only a very focal segmental

ncrease in mesangial matrix. There was segmental glomeru-ar basement membrane corrugation, but no spikes, holes, or

From the Department of Pathology, Vanderbilt Universityedical Center, Nashville, TN; Department of Pathology,osair Children’s Hospital; and Division of Nephrology,aptist Hospital East, Louisville, KY.Received February 16, 2005; accepted in revised form

pril 28, 2005.Originally published online as doi:10.1053/j.ajkd.2005.04.040

n October 5, 2005.Address reprint requests to Agnes B. Fogo, MD, Depart-

ent of Pathology, C3310, Medical Center North, Vander-ilt University Medical Center, Nashville, TN 37232-2561.-mail: agnes.fogo@vanderbilt.edu© 2005 by the National Kidney Foundation, Inc.0272-6386/05/4605-0027$30.00/0

idoi:10.1053/j.ajkd.2005.04.040

American Journal of Kidn82

plitting. One glomerulus showed a cellular crescent, and andditional glomerulus had a fibrocellular crescent withoutssociated necrosis. There was no endocapillary prolifera-ion, hyalinosis, segmental sclerosis, or fibrin thrombi. Thereas mild to moderate interstitial fibrosis involving 50% to0% of the sample, with proportional tubular atrophy. Manyubular profiles showed irregular epithelial cells with verynlarged nuclei, and occasional cells were multinucleatedith hyperchromatic nuclei (Figs 1 and 2). No viral inclu-

ions or other nuclear or intracytoplasmic inclusions toupport heavy-metal nephropathy were identified. There wasild lymphocytic infiltrate, predominantly in scarred areas,ithout polymorphonuclear cells or eosinophils. There wasild to moderate intimal fibrosis and medial thickening in

nterlobular arteries. Large arteries and arterioles also showededial thickening. Immunofluorescence microscopy showed

nly trace focal segmental mesangial staining for immuno-lobulin A (IgA) and IgM and 1� arteriolar and traceesangial staining for C3, with no significant staining with

gG, C1q, �, �, or polyvalent antisera. Electron microscopicxamination of 1 glomerulus showed glomerular basementembranes of normal thickness, with no lamellation or

ther irregularities. There were no subendothelial or subepi-helial deposits. Foot processes were largely intact, withnly approximately 20% effacement. The mesangial matrixhowed a mild occasional increase, without mesangial depos-ts. Tubular basement membranes did not show deposits.

Diagnosis. A diagnosis of karyomegalic nephropathy wasuggested if clinical data excluded lead or heavy-metaloisoning.

Clinical course and follow-up. After the biopsy result,he patient’s lead, arsenic, and mercury urinary levels wereetermined, and all were within normal ranges (arsenic, 20.7g/d [range, 0.0 to 63.9 mg/d]; lead, 2 mg/d [range, 0 to 31g/d]; and mercury, 3 mg/d [range, 0 to 15 mg/d]). The

atient was questioned further and denied use of any nonste-oidal anti-inflammatory drug, Chinese herb, or other pow-er use.

ase 2Clinical history. The patient’s brother, a 47-year-old

hite man who had chronic renal disease diagnosed since996, characterized by increased serum creatinine level, low-evel proteinuria, and negative standard serological test re-ults, underwent percutaneous renal biopsy in January 2001t an outside hospital. Additional history on this patient wasnavailable. His biopsy specimen showed findings similar tohose described for the first patient (Fig 3). Forty glomeruliere examined, 50% of which were obsolescent. The remain-

ng open glomeruli were normal, with only occasional peri-lomerular fibrosis. There was moderate tubular atrophy andnterstitial fibrosis, with proportional lymphoplasmocytic

nfiltrate containing rare polymorphonuclear cells. Tubular

ey Diseases, Vol 46, No 5 (November), 2005: pp 982-987

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ABNORMAL TUBULAR CELLS 983

pithelial cells showed nuclear enlargement with dark smudgyhromatin, without diagnostic viral-type inclusions or signsf heavy-metal toxicity. Immunofluorescence studies wereegative for IgA, IgM, C3, and C1q and showed only diffuseild linear accentuation of glomerular basement membranesith anti-IgG. Electron microscopic examination showed no

pecific glomerular abnormalities, with normal glomerularasement membranes without deposits.Diagnosis. A final diagnosis of karyomegalic interstitial

ephritis was made in both brothers.Clinical follow-up. The second brother underwent renal

ransplantation evaluation, and a series of laboratory testsas performed, including HLA haplotype and serological

ests for virus. Results for hepatitis C virus, hepatitis B virus,uman immunodeficiency virus types 1 and 2, and cytomeg-lovirus were negative. HLA typing showed HLA-A11,LA-A28, HLA-B35, and HLA-B37.

DISCUSSION

Karyomegalic nephropathy was described firsty Mihatsch et al1 in 1979. To date, 20 casesave been reported in the literature.2-7 The mainlinicopathologic features of cases reported toate are listed in Table 1. The major finding in

Fig 1. Scattered lymphoplasmacytic infiltrate andatient 1 (periodic acid–Schiff; original magnification �

he kidneys is the presence of markedly enlarged p

uclei in tubular epithelial cells of atrophic andonatrophic tubules. Although glomeruli seem toe spared, tubules of all nephron segments cane involved by these changes. Interstitial fibrosisnd chronic lymphocytic infiltrate also com-only are present.Cases usually are diagnosed in the second or

hird decade of life. Patients show impaired renalunction, usually with mild (protein �1 g/d)roteinuria. Renal function was normal in 3atients for whom the diagnosis was made at theges of 9, 12, and 32 years.3,6,7 There often is aistory of recurrent upper respiratory tract infec-ions in patients with karyomegalic nephropathy,resent in 10 of the 20 cases reported. It is notlear whether this respiratory symptom is a con-equence of the uremia or a manifestation of arimary common underlying cause. However,he latter possibility is favored by the observa-ion that infective episodes preceded the develop-

ent of a well-established uremic state in many

itial fibrosis and abnormally enlarged tubular nuclei;

interst200).

atients. In our first patient, there was no history

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ROSSINI ET AL984

f recurrent respiratory infections; however, therother experienced chronic sinusitis.Systemic involvement has been described in 6

atients reported in the literature as either mildepatopathy shown by increases in serum transami-ase levels or biopsy-proven karyomegaly in or-ans other than the kidneys. In 3 patients exam-ned by means of multiple-organ biopsy orutopsy, enlarged nuclei were described inchwann cells of peripheral nerve, smooth muscleells of vessels and bowel, cells of the bile ductpithelium, Kupffer cells, and, less obviously,ndothelial and adventitial cells of vessels, alveo-ar epithelial cells, and astrocytes of the brain.1,2

owever, a full examination with multiple biop-ies has been performed only occasionally. In 2atients in whom such examination was per-ormed, there was no evidence of karyomegalichanges in other organs. In 1 patient with karyo-egalic nephropathy and elevated liver enzyme

evels, liver biopsy findings were normal.5 In aecond patient with karyomegalic nephropathy

Fig 2. Tubular nuclei are remarkably enlarged, buchiff; original magnification �400).

ho died of pneumonia after transplantation, no H

xtrarenal karyomegalic changes were present.6

herefore, although the presence of karyo-egaly in the kidney is associated with func-

ional impairment in all cases, it is not clearhether the presence of similar changes in otherrgans affects their normal function. In our pa-ients, there was no apparent systemic involve-ent in either brother in that systemic clinical or

aboratory abnormalities were not noted.Very little is known about the pathogenesis of

his disease. Karyomegaly has been linked to aefect in cell division. Spoendlin et al3 analyzedhe nuclear proliferation–associated markers pro-iferating cell nuclear antigen/cyclin and Ki-67o investigate this hypothesis. Although theirtudy found a low labeling index for Ki-67 andigh labeling index for proliferating cell nuclearntigen/cyclin in these cells, suggesting inhibi-ion of mitosis, other studies failed to confirmhese data.5,6

A familial clustering of patients was describedn 12 of 20 cases previously reported. Analysis of

ut viral or lead inclusions; patient 1 (periodic acid–

LA subtypes in the previous patients showed

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ABNORMAL TUBULAR CELLS 985

he presence of HLA-A9 in 8 patients and HLA-35 in 7 patients, whereas HLA-A2 was re-orted in 5 patients. In our patients, HLA exami-ation was available for only 1 brother, who,nterestingly, showed the presence of the HLA-35 allele. The presence of these HLA-A9 andLA-B35 haplotypes in association with karyo-egaly and with familial clustering in 6 of 9

atients described suggest the presence of aossible inherited defect. The prevalence of these

alleles in association is uncommon in theeneral population.8 However, other patients haveot shown either HLA-A9 or HLA-B35 haplo-ype linkage.6 The possibility that a commonnvironmental agent could account for the occa-ional familial clustering of patients cannot bexcluded. An environmental effect also does notxclude a genetic contribution because the latterould provide a permissive, but not obligate,ackground for risk for disease that may require

Fig 3. Findings in patient 2, the brother of patient 1,uclei, focal interstitial fibrosis, and scattered intersriginal magnification �100).

dditional factors to fully develop. c

The diagnosis of karyomegalic nephropathy isade when other possible causes for nuclear

hanges seen in the biopsy specimen are reason-bly excluded. Nuclear changes with enlarge-ent are not uncommon in renal biopsy speci-ens. Enlarged nuclei can be seen frequently in

he presence of such viral infections as cytomeg-lovirus or polyoma, especially in immunocom-romised patients.9-11 However, in these set-ings, nuclei often show viral inclusions, in whichase, specific immunohistochemical studies cane pursued to confirm the diagnosis of viralnfection. Other possible causes of karyomegalynclude heavy-metal intoxication,12-14 irradia-ion,15 antimitotic therapy,16 or exposure to suchycotoxins as ochratoxin A.4,7,17

Ochratoxin A is a mycotoxin produced by aumber of Aspergillus and Penicillum speciesnd represents a common contaminant found in aariety of foods, especially in underdeveloped

arkably similar, with focal markedly enlarged tubularmphoplasmacytic infiltrate (hematoxylin and eosin;

are rem

ountries and rural areas. Ochratoxin causes re-

Table 1. Clinicopathologic Characteristics of Patients With Karyomegalic Nephropathy

Reference

Age ofOnset

(y) SexCountry of

OriginExposure to

NephrotoxinsSerum Creatinine

mg/dLProteinuria

(g/24 h)Systemic

InvolvementRecurrentInfections HLA

FamilyHistory

Mihatsch et al,1

197926 M Switzerland Lead, phenacetin 4.0 0.3-0.9 – � A9-B35 –29 M Italy — 5.0 1.0 � � A2,A9-B35,B21 �26 M Italy — 3.9 0.6-0.9 � � A2,A9-B35,B21 �

Moch et al,2

199430 M Italy — Not available Not available � Not available Not available –

Spoendlin etal,3 1995

27 M Switzerland — 2.5 0.9 – � A9-B35 �12 M Switzerland — Normal Normal – � A9-B35 �39 F Switzerland — 1.9 0.2 – � A2,A26-B39 –24 F Spain — 1.9 0.6 – – A9,A11-B7,B52 –

Godin et al,4

199632 M France Ochratoxin 1.8 Mild � – A9,A24-B35 �42 F France Ochratoxin 1.7 Mild � – A9,A24-B35 �

Vadiaka et al,5

199834 M Greece — 1.9 0.35 � � A1,A19-B52,B49 –

Bhandari et al,6

200230 F Australia — 2.8 1.0-1.5 – – A24,A32-B14,B18 �21 M Australia — 2.1 0.7 – � A2,A29-B44,B47 –38 M Australia — Not available Not available – – A1,A2-B8,B15 �29 M Australia — 2.3 0.1 – � Not available –9 F Australia — Normal Not available – – Not available –

37 F Australia — 2.2 0.25 – – Not available �Hassen et al,7

200448 M Tunisia Ochratoxin 4.0 0.76 � – A3, A28-B27,B35, DR 7/52 �*42 M Tunisia Ochratoxin 9.3 0.50 � � A3, A28-B27,B35, DR 7/11 �32 F Tunisia Ochratoxin 48 0.22 – – A3, A40-B27,B35, DR 7/52 �

Current report 41 M United States — 2.0 0.3 – � Not available �43 M United States — 2.9 0.7 – – A11,A28-B35,B37 �

NOTE. To convert creatinine in mg/dL to �mol/L, multiply by 88.4.*These 3 patients are siblings. R

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ABNORMAL TUBULAR CELLS 987

al carcinoma in experimental rodent modelsnd a form of nephropathy in pigs18 that closelyesembles Balkan nephropathy, a human diseaseith similar nuclear changes endemic in thealkan area. Ochratoxin also induces karyome-alic nephritis in rat models.19-21 Ochratoxinas identified in at least 4 cases of karyomegalicephropathy reported to date.4,7 Of note, studiesor ochratoxin in blood or urine were performedn only a minority of the patients reported; there-ore, the true incidence of elevated ochratoxinevels in these patients is not known. Recently,assen et al7 described 3 siblings in Tunisia witharyomegalic nephropathy. Two siblings had highchratoxin A levels in urine, and all 3 patientshowed high concentrations of mycotoxin inlood. Interestingly, all shared the same HLA-27/B35 haplotype. The local community, con-

isting of 4 families with 21 members, also wastudied. Although no additional cases of karyo-egalic nephropathy were identified in other

amilies, high ochratoxin A levels also wereound in members of other families and in theood this community shared. These data suggesthat the presence of HLA-B27/B35 might repre-ent a genetic risk factor that, with an environ-ental agent, can cause disease.In conclusion, in our patients with nonspecific

linical findings suggesting a chronic interstitialisease, a specific morphological diagnosis ofaryomegalic nephropathy was made from renaliopsy specimens. Our studies do not shed lightn a possible contribution of ochratoxin becausehese levels were not measured and reports areot available from the geographic region to sup-ort whether ochratoxin could be involved. Theresence of the HLA-B35 allele in the 1 brotherho underwent testing further supports the hypoth-

sis of a genetic susceptibility to this disorder.

REFERENCES1. Mihatsch MJ, Gudat F, Zollinger HU, Heierli C, Tholen

, Reutter FW: Systemic karyomegaly associated withhronic interstitial nephritis. A new disease entity? Clinephrol 12:54-62, 19792. Moch H, Spondlin M, Schmassmann A, Mihatsch MJ:

ystemic karyomegaly with chronic interstitial nephritis.iscussion of the disease picture based on an autopsy case.athologe 15:44-48, 19943. Spoendlin M, Moch H, Brunner F, et al: Karyomegalic

nterstitial nephritis: Further support for a distinct entity andvidence for a genetic defect. Am J Kidney Dis 25:242-252,

995 w

4. Godin M, Francois A, Le Roy F, et al: Karyomegalicnterstitial nephritis. Am J Kidney Dis 27:166, 1996

5. Vadiaka M, Sotsiou F, Koufos C: A case of systemicaryomegaly associated with interstitial nephritis. Ann Mednterne 149:291-294, 1998

6. Bhandari S, Kalowski S, Collett P, et al: Karyomegalicephropathy: An uncommon cause of progressive renalailure. Nephrol Dial Transplant 17:1914-1920, 2002

7. Hassen W, Abid-Essafi S, Achour A, et al: Karyo-egaly of tubular kidney cells in human chronic interstitial

ephropathy in Tunisia: Respective role of ochratoxin A andossible genetic predisposition. Hum Exp Toxicol 23:339-46, 20048. American Society of Histocompatibility and Immuno-

enetics: Available at: http://ashi-hla.org/publicationfiles/rchives/prepr/mori_ab.htm. Accessed: March 20, 2005

9. Kashyap R, Sapiro R, Jordan M, Randhawa PS: Thelinical significance of cytomegaloviral inclusions in thellograft kidney. Transplantation 67:98-103, 1999

10. Battegay EJ, Mihatsch MJ, Mazzucchelli L, et al:ytomegalovirus and kidney. Clin Nephrol 30:239-247,98811. Nickeleit V, Hirsch HH, Binet IF, et al: Polyomavirus

nfection of renal allograft recipients: From latent infectiono manifest disease. J Am Soc Nephrol 10:1080-1089, 1999

12. Bonucci E, Silvestrini G: Ultrastructural studies inxperimental lead intoxication. Contrib Nephrol 64:93-101,98813. Beaver DL: The ultrastructure of the kidney in lead

ntoxication with particular reference to intranuclear inclu-ions. Am J Pathol 39:195-208, 1961

14. Choie DD, Richter GW: Lead poisoning: Rapid for-ation of intranuclear inclusions. Science 177:1194-1195,

97215. Otsuka M, Meistrich ML: Cell proliferation and ab-

ormal nuclei induced by radiation in renal tubule epithe-ium as an early manifestation of late damage. Radiat Res23:285-291, 199016. Dahlgren S, Holm G, Svanborg N, Watz R: Clinical

nd morphological side-effects of busulfan (Myleran) treat-ent. Acta Med Scand 192:129-135, 197217. Kuiper-Goodman T, Scott PM: Risk assessment of

he mycotoxin ochratoxin A. Biomed Environ Sci 2:179-48, 198918. Krogh P: Role of ochratoxin in disease causation.

ood Chem Toxicol 30:213-224, 199219. Maaroufi K, Zakhama A, Baudrimont I, et al: Karyo-egaly of tubular cells as early stage marker of the nephro-

oxicity induced by ochratoxin A in rats. Hum Exp Toxicol8:410-415, 199920. Baudrimont I, Betbeder AM, Gharbi A, Pfohl-

eszkowicz A, Dirheimer G, Creppy EE: Effect of superox-de dismutase and catalase on the nephrotoxicity induced byubchronical administration of ochratoxin A in rats. Toxicol-gy 89:101-111, 199421. Mantle PG, McHugh KM, Adatia R, Heaton JM,

ray T, Turner DR: Penicillium aurantiogriseum-induced,ersistent renal histopathological changes in rats; An experi-ental model for Balkan endemic nephropathy competitive

ith ochratoxin A. IARC Sci Publ 115:119-127, 1991