Primary hyperoxaluria in a pediatric dental patient:case reportMohammed M. Rahima, DDS, MS, PhD Michael P. DiMauro, DDS

CASE REPORTS

AbstractA case is presented in which primary hyperoxaluria and oxalosis in a 14-year-old Caucasian female were

diagnosed. Generalized root resorption resulted in a remarkable mobility of her maxillary central and lateralincisors, although no bone loss was noted. The management of the patient’s dental concerns in this rareheritable metabolic disorder consisted of removing the maxillary incisor teeth and placing two sequentialprostheses, which the patient tolerated well. A history of trauma to the maxillary incisors was ruled out, sothis case adds previously unreported information to our knowledge about the effect of oxaluria on teeth andoral tissues. (Pediatr Dent 14:260-62, 1992)

Introduction and Literature ReviewPrimary hyperoxaluria, a rare autosomal recessive

disorder of glyoxalate metabolism, most likely enzy-matic, manifests as an excessive calcium oxalatemonohydrate biosynthesis and deposition within themesodermal tissue of the body.1-3 The disorder is char-acterized by nephrolithiasis, nephrocalcinosis, and re-nal oxalate deposits. Even though nephrocalcinosis isthe predominant and early clinical manifestation,extrarenal deposits of calcium oxalate monohydrate invarious, but apparently selective target tissues, are acommon persistent finding. These tissues may include,but are not restricted to, the kidneys, heart, oculartissues, thyroid, bone, lymph nodes, walls of arteriesand veins, brain, dentin, dental pulps, and salivaryglands.4 When extrarenal deposits of calcium oxalateare noted, the disorder is labelled as oxalosis. Calciumoxalate may have less of a tendency to form deposits inother tissues, but other tissues are not necessarily im-mune.

As the disease progresses, partial to complete loss ofrenal function due to nephrolithiasis is encountered,making renal dialysis necessary. Kidney transplanta-tion is attempted frequently with varying degrees ofsuccess. The weight-bearing areas and joint spaces be-come affected as the oxalate accumulates in the syno-vial tissues and fluid of the joints, often immobilizingthe patient. Anti-inflammatory and analgesic drugs areadministered for pain control.

Dental and periodontal findings associated with pri-mary hyperoxaluria and oxalosis include extensive in-filtration of crystals in the pulps of developing teeth, inthe marrow spaces of the alveolar bone, in the gingivalcorium, and in the periodontal ligament.5, 6 Crystallinecalcium oxalate deposits within the periodontal liga-ment provoke a granulomatous foreign-body reactionwhich results in external root resorption, pulp expo-sure, and tooth mobility.7

Case ReportA 14-year-old Caucasian female, diagnosed at 7 years

of age with end-stage renal disease and oxalosis, pre-sented to the Rainbow Babies and Children’s PediatricDental Clinic with a chief complaint of painful, mobilemaxillary anterior teeth with no history of trauma. Thepatient had received a light-cured acrylic compositesplint from the maxillary right lateral incisor to the leftlateral incisor from a local practitioner approximatelysix weeks earlier, but then was referred for definitivetreatment after the splint failed as a result of insufficientenamel etching and/or excessive mobility of the inci-sors.

Hyperoxaluria was diagnosed based on a significant24-hr oxalate excretion (159 mg/24 hr). There was family history of hyperoxaluria. The patient receivedhemodialysis three times weekly while awaiting a renaltransplant. Daily medications included 3000 units ofheparin to maintain the patency of the Scribner Shuntplaced in the left ankle, 0.5 mg/kg cyclosporin, 10 mgprednisone every other day, 50 mg hydrochlorothiazide,400 mg Tagamet® (Smith Kline and French LaboratoryCo., Carolina, Puerto Rico), 1.0 mg folic acid, 100 mgPyridoxine® hydrochloride (Forest Pharmaceuticals,Inc., St. Louis, MO), 810 mg Uro-mag® (Blaine Co., Inc.,Fort Mitchell, KY) in divided doses, and 250 mg Neutro-phos® (Willen Drug Co., Baltimore, MD). The patientwas nonambulatory and short, with yellowish brownpapillary-like lesions scattered on the skin due tosubdermal oxalate crystal deposits. The patient washepatitis B-positive, but HIV negative.

Radiographs exposed at the time of presentationrevealed unremarkable bony architecture, generalizedloss of lamina dura, and extensive external root resorp-tion of the maxillary central and lateral incisors (Fig 1,next page). A lateral periapical film showed a markedprocumbency of the maxillary incisors, and a panoramic

260 PEDIATRIC DENTISTRY: JULY/AuGuST, 1992 N VOLUME 14, NUMBER 4

Figl.Periapical radiograph demonstratesextensive resorption of the roots of themaxillary permanent central incisors.External root resorption of the maxillarylateral incisors also is evident.

film yielded noadditional un-usual findings.No bone resorp-tion or bone losswas noted else-where in thedentition.

Both maxil-lary central inci-sors demon-strated markedmobility and se-vere discolora-tion, while themaxillary lateralincisors were ofnormal colorand only slightlymobile. None ofthe maxillary in-cisors were sen-sitive to percus-

sion, but all exhibited some sensitivity to masticatoryforces. Vitality testing of the incisors was not performed,because a periodontal consultation in conjunction withexisting radiographs determined the teeth to benonsalvageable. All other oral tissues appeared normaland healthy. Consultations with the patient's primaryphysician and hematologist before treatment led to thedecision to manage the case under general anesthesia; abone marrow biopsy also was scheduled to be per-formed.

Before the surgery, an immediate partial prosthesiswas fabricated to act as a surgical stent and improvepatient acceptance postoperatively. The surgery was onthe alternate day of hemodialysis, so that the heparinadministration would not affect hemostasis. The pa-tient received penicillin GIV before and after the proce-dure as prophylaxis against bacterial infection of theshunt. Prednisone administration was discontinued onthe day of the surgery only, due to intravenous admin-istration of corticosteroids as a supplement.

Maxillary central and lateral incisors were extracted,and the gingiva excised and thinned under local anes-thesia for hemostasis and sent with the teeth for evalu-ation. Sutures were placed in an interrupted fashion,and the interim prosthesis also was placed. The postop-erative course was uneventful, and the patient wasdischarged the same day.

The permanent prosthesis, with Adams clasps on themaxillary permanent first molars and ball clasps be-tween the premolars, was delivered 21 days postopera-tively and accepted well. Since the surgery, the patient

has had a combination kidney and liver transplant toimprove her condition.

Histological FindingsThe soft tissue fragments show extensive, strongly

birefringent crystalline deposits and an associated for-eign body giant cell reaction (Figs 2 and 3, next page)limited to the underlying connective tissue of the gin-giva. The individual deposits are roughly circular inshape, with needle-like crystals projecting from theircenters, giving rise to the so-called "spokes on a wheel,"and giant cells clearly are visible surrounding eachcrystal (Fig 3, arrows). These crystalline masses areinterpreted as calcium oxalate crystals. Calcium oxalatecrystals and the associated foreign body giant cell reac-tion were not observed within the decalcified teeth.However, the generalized root resorption and thick-ened predentin layer suggest the dental changes associ-ated with oxalosis.

DiscussionBoth primary and secondary forms of hyperoxaluria

are characterized by calcium oxalate deposition withinthe mesenchymal tissues of the affected individual. Theprocess of oxalate deposition is not understood fully.However, Brancaccio et al.9 suggested that higherplasma oxalate levels and alterations in vascular per-meability may be responsible for calcium oxalate depo-sition. Normal pediatric values for urinary oxalate ex-cretion are usually between 10 mg and 50 mg per 24 hr.Individuals with primary hyperoxaluria may approacha value of approximately 240 mg per 24-hr period.5' ̂

The findings in this case are consistent with those ofGlass5 and Wysocki et al.6 Fantasia et al.^ offer a pos-sible explanation for the accumulation of oxalate crys-tals in the periodontium.7 Alteration in capillary per-meability in the areas of inflammation leads to theescape of plasma proteins and oxalates into the sur-rounding tissues. These crystals, in turn, accelerate theinflammatory reaction (which ultimately resulted inthe external root resorption seen in this condition).

Patients with primary hyperoxaluria often die earlyin life from renal failure caused by blockage of renaltubules.11 Very little is known about this disease, be-cause the survivor pool is so small. However, modernlife-sustaining measures such as hemodialysis and peri-toneal dialysis are allowing patients with primaryhyperoxaluria and oxalosis to enjoy much longer andfuller lives; thus, dentists are seeing previouslyunencountered manifestations of this disorder. Thefinding of root resorption in this case report is new, butmay be a sequela of the disease, since neither the childnor her parents confirmed a recent history of trauma tomaxillary teeth.

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Fig2. Photomicrograph of a section cut from the biopsy specimenobtained from the patient's gingiva. Aggregates of birefringentcalcium oxalate crystals (arrow heads) in the underlyingconnective tissue is evident. E: gingival epithelium; CT:Underlyingconnectivetissue. (H &Estain;original magnificationx100).

Fig 3. Photomicrograph of a higher magnification from Fig 1above showing an individual rossette of calcium oxalate crystalsurrounded by a connective tissue core associated withgranulomatous foreign body reaction. Note the presence ofgiant cells at the periphery of the rosette (arrow heads). (H & Estain; original magnification x400).

Dr. Rahima is in private practice, Palos Hills, IL. Dr. DiMauro is inprivate practice, Orlando, Florida. Reprint requests should be sent to:Dr. Mohammed M. Rahima, Family Dental Center, 10500 SouthRoberts Road, Palos Hills, IL 60465.

1. Wyngaarden JB, Elder TD: Primary hyperoxaluria and oxalosis.In The Metabolic Basis of Inherited Diseases, 2nd ed, JB Stanbury,JB Wyngaarden, and DS Fredrickson eds. New York: McGraw-Hill Book Co, 1966, pp 189-201.

2. Williams HE, Smith LH Jr: Disorders of oxalate metabolism.Am J Med 45:715-35,1968.

3. Williams HE, Smith LH: Primary hyperoxaluria. In The Meta-bolic Basis of Inherited Diseases, 4th ed, JB Stanbury, JBWyngaarden, and DS Fredrickson eds. New York: McGraw-Hill Book Co, 1978, pp 182-204.

4. Milgram JW: Chronic renal failure, recurrent secondaryhyperparathyroidism, multiple metaphyseal infarctions, andsecondary oxalosis. Bull Hosp Joint Dis 35:118-44,1974.

5. Glass RT: Oral manifestations in primary hyperoxaluria andoxalosis: report of a case. Oral Surg 35:502-59,1973.

10.

11.

Wysocki GP, Fay WP, Ulrichsen RF, Ulna RA: Oral findings inprimary hyperoxaluria and oxalosis. Oral Surg 53:267-72,1982.Moskow BS: Periodontal manifestations of hyperoxaluria andoxalosis. J Periodontol 60:271-78,1989.Fantasia JE, Miller AS, Chen SY, Foster WB: Calcium oxalatedeposition in the periodontium secondary to chronic renalfailure. Oral Surg 53:273-79,1982.Brancaccio D, Poggia A, Ciccarelli C, Bellini RF, Galmozzi C,Poletti I, Maggiore Q: Bone changes in endstage oxalosis. Am JRoentgenol 136:935-39,1981.Hockaday TDR, Frederick EW, Clayton JE, Smith LR Jr: Studieson primary hyperoxaluria. II. Urinary oxalate, glycolate andglyoxylate measurement by isotope dilution methods. J LabClin Med 65:677-87,1965.Breed A, Chesney R, Friedman A, Gilbert E, Langer L, LattoracaR: Oxalosis-induced bone disease. A complication of transplan-tation and prolonged survival in primary hyperoxaluria. J BoneJoint Surg [Am] 63-A:310-16,1981.S

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