Tophi Research Articles

Gouty Tophi

BACKGROUND Digital lesions can have a broad differential diagnosis. Squamous cell carcinoma (SCC), the most common digital malignant neoplasm, must be excluded as the cause of persistent digital lesions causing nail dystrophy. OBJECTIVE To describe a patient with a periungual hyperkeratotic lesion on the left fifth digit which, upon initial dermatopathologic examination, appeared to be a malignancy. However, on further biopsy, the lesion proved to be a gouty tophus. METHODS Case report and literature review. RESULTS An 84-year-old white man presented with a hyperkeratotic papule on the lateral proximal nail fold of the left fifth digit, which resulted in nail dystrophy for 1 year. Similar lesions were present on several other digits which did not affect the nail plate. Initial biopsy was consistent with actinic keratosis and was treated with cryotherapy. When the lesion persisted, repeat biopsy was performed, demonstrating fragments of squamous epithelium with focal atypia and an infiltrative growth pattern. SCC could not be excluded and the patient was referred for Mohs micrographic surgery (MMS) consultation. An excisional biopsy was performed and a white chalky material was observed at the base of the defect. Histopathology confirmed a gouty tophus. The patient was referred to his primary care physician and was treated with allopurinol. CONCLUSION This is the first report of gouty tophus of the periungual region presenting as a hyperkeratotic lesion. Initial clinical diagnosis favored SCC and histologic evidence suggested a possible early SCC. This lesion can be confused with digital squamous cell carcinoma. The presence of pseu- docarcinomatous hyperplasia may complicate accurate diagnosis.

Fine-needle aspiration cytology of articular and periarticular lesions.

The cytologic diagnosis of joint and articular surface-based lesions traditionally has been accomplished by examination of fluids or effusions. Although exfoliative cytology remains an accurate diagnostic test, not all joint-based lesions will produce effusions that are amenable to this type of examination. Fine-needle aspiration (FNA) represents an excellent alternative to traditional cytologic or histologic methods of diagnosis in joint pathology. The authors reviewed FNA materials for the period 1992-2001 from lesions of joint spaces and periarticular soft tissues. All diagnoses based on cytologic materials that were included in this study were confirmed with histologic follow-up. Cytologic and histologic materials were prepared using standard methods. The authors found six relatively common lesions that were amenable to diagnosis by FNA. These included rheumatoid nodule, gouty tophi, ganglion cysts, pigmented villonodular synovitis, synovial chondromatosis, and synovial sarcoma. There are potential pitfalls in discriminating gout from pseudogout and synovial chondromatosis from chondrosarcoma. In most instances, mass-producing lesions of the joint space or the periarticular soft tissues can be diagnosed successfully by FNA. The common lesions are easily recognizable and are cytologically distinctive.

Pathologic quiz case: a soft tissue mass with bone destruction. Gouty tophus.

Pathologic quiz case: a soft tissue mass with bone destruction. Gouty tophus.

Gouty tophus of the patella evaluated by PET imaging

We report a case of gouty tophus of the patella, a rare lesion, which was evaluated using positron emission tomography (PET). This modality, which uses a combination of an amino-acid analog emitter, l-[3-18F]-alpha-methyl tyrosine (FMT), which neglects malignancies, and a glucose analog emitter, 18F-fluoro-2-deoxy-d-glucose (FDG), which neglects benign lesions, simulating the radiographic findings, may be useful for the preoperative evaluation of gouty tophus occurring in patella partita, including detection, differentiation from malignant tumors, and possible pathogenetic diagnosis.

Tophaceous Gout of the Spine Mimicking Epidural Infection: Case Report and Review of the Literature

OBJECTIVE AND IMPORTANCE Tophaceous gout uncommonly affects the axial skeleton. The clinical presentations of gout of the spine range from back pain to quadriplegia. Gout that presents as back pain and fever may be difficult to distinguish from spinal infection. We present a case of a patient with tophaceous gout of the lumbar spine who was initially diagnosed with and treated for an epidural infection. The clinical and diagnostic features of tophaceous gout of the spine are reviewed. CLINICAL PRESENTATION A 70-year-old man presented with a 2-day history of fever and back pain. A physical examination revealed that he had flank tenderness and evidence of polyarthritis affecting the elbows, knees, and right first metatarsophalangeal joint. A magnetic resonance imaging scan of the patient’s lumbar spine showed an extensive area of abnormal gadolinium enhancement of the paramedian posterior soft tissues from L3 to S1 with an area of focal enhancement extending into the right L4–L5 facet joint. INTERVENTION A laminectomy was performed at L4–L5, and a chalky white material in the facet joint was found eroding into the adjacent pars intra-articularis. Light and polarizing microscopy confirmed the presence of gouty tophus. No evidence of infection was found. CONCLUSION Gouty arthritis of the spine is rare. Thirty-seven previous cases have been reported. When the clinical presentation includes acute back pain and fever, differentiation of spinal gout from spinal infection may be difficult. The clinical suspicion of spinal gout may lead to the correct diagnosis by a less invasive approach than exploration and laminectomy.

Cutaneous Angiosarcoma Arising in a Gouty Tophus

Rare cases of angiosarcoma have been reported to arise in the setting of retained foreign material or in association with arteriovenous fistulae. No previous case of angiosarcoma, or any other malignancy, has been reported to arise with a gouty tophus. We present a case of an 86-year-old man with a high-grade angiosarcoma that arose within a long-standing tophus.

Fine‐needle aspiration biopsy of gouty tophi: Lessons in cost‐effective patient management

Gout, a disease resulting from the effects of hyperuricemia and a crystal-induced arthropathy, may produce soft tissue masses (tophi), which mimick neoplasia clinically and radiographically. We have recently diagnosed three cases of gouty tophus, two of which were clinically suspected to represent sarcomas, by fine-needle aspiration biopsy (FNAB) after extensive radiologic and clinical evaluation. There were two women and one man, aged 71, 73, and 50 yr, with palpable soft tissue masses that involved the right forearm, right hand, and right foot, respectively. Biopsies were obtained by using 25-gauge needles without the aid of general anesthesia. Morphologically, aggregates and disassociated slender, needle-shaped crystals were abundant and easily recognized on both Diff-Quik and Papanicolaou stains. By using a polarizing microscope with a first-order red compensator, the crystals showed negative birefringence, characteristic of sodium urate. Benign-appearing histiocytes, foreign-body-type giant cells, neutrophils, and amorphous debris were scattered among the diagnostic crystals. The diagnosis of gouty tophus can be easily established with FNAB in conjunction with compensated polarizing microscopy. Application of FNAB in the initial evaluation of appropriate soft-tissue masses provides a cost-effective diagnostic method, preventing more costly and often unnecessary clinical and radiologic tests. Diagn. Cytopathol. 17:30–35, 1997. © 1997 Wiley-Liss, Inc.

Periosteal gouty tophi of the anterior mid tibia

We report the occurrence of gouty tophi in a 45-year-old man involving the surface of the mid tibia overlying the site of a remote fracture.

MR imaging of tophaceous gout.

MR imaging is not routinely used for evaluation of tophaceous gout. However, gout may present clinically in an atypical, unusual, or confusing manner. A gouty tophus occasionally mimics an infectious or neoplastic process, and MR imaging may be obtained under these circumstances. The purpose of this study was to determine the MR imaging characteristics of intraosseous and soft-tissue tophi. We identified 13 MR imaging examinations performed during a 27-month period on nine patients with gouty arthritis. All were men 42-70 years old. T1-, proton density-, and T2-weighted spin-echo MR images were obtained for all the examinations. Nine examinations included contrast-enhanced MR images. The findings were then evaluated, as were the corresponding radiographs. Five patients presented with articular involvement, three patients with an isolated soft-tissue mass, and one patient with persistent soft-tissue swelling. The duration of symptoms ranged from 3 months to more than 20 years. Nearly all the tophi were of intermediate signal intensity on T1-weighted images. On T2-weighted images, three sites revealed an overall increase in the signal intensity of the tophi, whereas 10 studies showed a heterogeneous decrease in signal intensity. All but one tophus showed homogeneous enhancement. Erosion of adjacent bone, synovial pannus, joint effusion, soft-tissue edema, and bone marrow edema were common associated findings. The MR appearance of tophi in patients with tophaceous gout is constant on T1- but quite variable on T2-weighted images. This variability in signal intensity could be related to calcium within a tophus. Tophaceous gout should be considered in the differential diagnosis when a mass reveals heterogeneously low to intermediate signal intensity, particularly if the adjacent bone shows typical erosive changes or if other joints are involved. When faced with this situation, radiologists may find it helpful to obtain a further clinical history and recommend evaluating the patient's serum urate level.

MR imaging in gout

The appearance of gouty tophus in magnetic resonance imaging (MRI) is characteristic. On T1- and T2-weighted SE images, the signal intensity of tophaceous lesions is similar to that of muscles. According to the histology, T2-weighted SE images demonstrate extremely hyperintense signals, which reflect the high protein content in the amorphous center of the tophus. The microscopic urate crystals deposited there have no MRI signal and are of no further diagnostic impact. Vascularized granulation tissue surrounding the tophus center enhance after intervenous application of contrast agents (Gadolinium). The inflamed tophus is associated with local edema, causing high signal intensity. MRI is superior to plain radiography for early detection of intraosseous tophi. Involvement of anatomical structures such as ligaments and tendons can be evaluated sufficiently. For peripheral joints, axial slice orientation is most helpful.

Intraosseous gout of the foot: An unusual case report

The literature is abundant with cases of crystalline deposition disorders of the lower extremity. Although acute gout and gouty tophi have commonly been described in the medical literature, findings of gouty deposits within the bone itself has been seldom reported. This paper presents an unusual case of intraosseous gout and its etiology and treatment.

Blood Pressure Monitoring in Hemiplegic Patients

To the Editor: We are frequently asked which arm should be used to measure blood pressure in patients with hemiplegia. We have observed that blood pressure measurements from the hemiplegic arms of post-stroke patients do not correlate well with measurements from the nonhemiplegic arm. The following two cases illustrate that finding. Patient 1 is a 69-yr-old male who suffered a stroke 2 yr prior to sustaining a femoral neck fracture. Residuals from the stroke included mild dementia and right hemiparesis with spasticity. The blood pressure in the hemiparetic arm was 114/68 mm Hg, whereas the blood pressure in the nonparetic arm was 157/73 mm Hg. The radial pulse was also weaker in the paretic arm than the nonparetic arm. Patient 2 is a 75-yr-old male who presented for colon resection. He had suffered a stroke with residual right hemiparesis 2 yr prior to the current surgery. Blood pressure was 100/60 mm Hg in the paretic arm and 150/74 mm Hg in the nonparetic arm. Yagi et al. [1] measured blood pressure, both noninvasively and invasively, in 47 patients after stroke. They found that blood pressure was significantly higher in the paretic arm than in the nonparetic arm. Panayiotou et al. [2] measured blood pressure in 15 patients with acute hemiparesis and flaccidity and found the systolic and diastolic blood pressures to be higher in the paretic arm in 8 of 15 patients and lower in 7 of the 15 patients. Dewar et al. [3] measured blood pressure in 103 hemiplegic patients and found blood pressure in the paretic arm to be higher if it was spastic and lower if it was flaccid. They concluded that muscle tone influences extremity blood pressure. A number of investigators, including Broe and Ofner [4], have described vasomotor changes affecting the upper extremities in patients after a stroke. These changes may affect the paretic arm, the nonparetic arm, or both. We measured blood pressure in 14 patients with hemiplegia. Nine patients had spasticity on the affected side and five had flaccidity. All five of the patients with flaccid arms had lower blood pressure in the flaccid arm compared with the normal arm. Five of the nine patients with spasticity had higher blood pressure in the paretic arm, four had lower blood pressure in the paretic arm, and one patient had equal blood pressures. Two patients in whom we invasively measured blood pressure in the paretic arm demonstrated blood pressure that was not different from the blood pressure measured noninvasively in the unaffected arm. A large number of chronic changes such as clubbing, retardation of nail growth, edema, osteoporosis, fractures, arthritis, shoulder dislocation, frozen shoulder, periarticular calcification, muscle wasting, temperature differences, and deep vein thrombosis can occur in paretic extremities after a stroke. Interestingly, some pathologic changes such as rheumatoid arthritis and gouty tophi do not affect paretic limbs after a stroke [5]. Because of the large and inconsistent differences in blood pressure in the arms of patients with hemiparesis, we suggest that measuring blood pressure in the nonparetic arm of poststroke patients will provide a more reliable monitor of blood pressure during anesthesia. S. S. Moorthy, MD Larry Davis, MS R. V. Reddy, MD Stephen F. Dierdorf, MD Departments of Anesthesia and Neurology Indiana University School of Medicine Indianapolis, IN 46202

Tophaceous gout of the spine causing spinal cord compression.

Tophaceous gout of the spine rarely causes spinal cord compression. Only eight cases have been reported previously. We report a further case presenting with progressive quadriparesis caused by gouty tophi at C1, treated successfully by decompressive laminectomy and internal fixation. This case and the previously reported cases are reviewed.

開口障害をきたした顎関節部痛風結節の１例

Gout is a chronic metabolic disorder characterized by acute exacerbations of joint pain and swelling associated with elevated uric acid in the blood. The attacks result from deposition of crystals of monosodium urate in and around the joints. However, gout of the temporomandibular joint is rare. The case reported here had a gouty tophus arising on the temporomandibular joint which was associated with trismus.

Identification of pathological mineral deposits by Raman microscopy

Raman microscopy—the analysis of scattered photons after excitation—is well established in non-biological sciences for the identification of crystals. It shows promise in biological (clinical) specimens also, as demonstrated here in studies of synovial fluid, synovium, and gouty tophus, selected for their known content of sodium urate and calcium pyrophosphate crystals.

Uric acid metabolism in humans.

U RIG ACID, the end product of purine degradation in humans, gains clinical significance during states of increased production, decreased elimination, or increased renal excretion. Under these conditions urate can be deposited in tissues, or uric acid can precipitate in urine to cause uric acid nephrolithiasis. Disorders associated with abnormal uric acid homeostasis include Lesch-Nyhan syndrome, an inherited enzyme deficiency, gout, renal insufficiency, and increased cellular breakdown as in tumor lysis. This article focuses on the sources, production, and elimination of uric acid in man. Uric acid is a weak acid with a pKal of 5.75 due to a proton loss at position 9. l At the physiologic pH range of human serum, uric acid is a monovalent ion, but in urine, which has a more acidic pH range, it is mostly excreted as the free acid. Thus, when uric acid is deposited in tissues, as seen in tophaceous gout, the deposits are mostly monosodium urate utilizing the most abundant cation, and uric acid renal stones are largely free acid.* Uric acid can also lose a second proton at position 3 with a pKa, of 10.3.3 The solubility of uric acid, like the ionization, is pH-dependent, increasing as the pH and urate formation increase.4 In urine, at a pH of 5 .O, uric acid is soluble to 15 mg/dL and increases with increasing pH to 1,520 mg/dL at a pH of 8.0.5 From this information, it is obvious to see why urine alkalinization is an important therapy to prevent or dissolve uric acid kidney stones. To fully understand the metabolism of uric acid, it is important to begin with the source of uric acid, purines. There are three sources of purines: (1) dietary intake of foods containing purine bases, (2) de novo endogenous synthesis from nonpurine precursors, and (3) salvage of purine bases from endogenous catabolism. The major source of dietary purine is protein. The average diet contains 70 to 100 g/d of proteins.6 Hyperuricemia is induced by a high dietary intake of meats containing nucleic acid and mononucleotides.7.8 Zollner reported the intestinal absorption of mononucleotides to be complete, and the absorption of ribonucleotides to be only

Case report 591

It has been demonstrated in this 58-year old woman that osteoarthrosis OA coexisted in a hip with microscopic gouty tophi. It is demonstrated that the bone erosions around the hip in this case were due to OA and not gouty arthritis. It is believed that OA is not a consequence of gout and that such an association between gout and OA is exceptional. It is maintained that a true association exists between OA and ochronosis while a relationship may exist between OA and chondrocalcinosis, but the nature of this relationship is not clear.

24 FUNGALBIONICS-A NEW CONCEPT OF THE ETIOLOGY OF GOUT AND HYPERURICEMIA

Fungalbionics implicates fungi and fungal metabolites as the cause of gout/hyperuricemia. The mechanisms are not the usual patterns of invasive-type mycoses nor of mycotoxicoses, but rather incorporate occult features of both mechanisms. Gout and/or hyperuricemia can be induced in fowl by the mycotoxins oosporein, ochratoxin and by oosporein-produclng fungi. Gouty tophi have been induced in primates by aflatoxin. Fungi produce preformed uric acid, preformed urate crystals, lipoproteins, glycosaminoglycans and glutamates, excess of which are found in gout. Gouty tophi are granulomatous and possess all of the features of delayed hypersensitivity. Giant cells in avian and human gouty tophi contain asteroid bodies which are fungal in origin. Fungal-like spherules have been found in avian gouty lesions; cultural and immunological electron microscopy studies are in progress. The findings in acute gout are those of an acute infection. All drugs used in treating gout/hyperuricemia are antifungal. Griseofulvin, an antifungal antibiotic, is as effective as colchicine in gout. Both are antitubulins and arrest fungal cell division. Probenecid, allopurinol, corticosteroids, NSAIDS, possess antifungal activity. The fungalbionic concept gives a unitarian explanation of gout, hyperuricemia and related diseases and findings.

Aortic valvular tophus: identification by X-ray diffraction of urate and calcium phosphates.

A typical gouty tophus with birefringent, dichroic, needle shaped crystals was found in a resected calcified aortic valve on routine histological examination. The patient, an elderly man, had a long history of gout. X-ray diffraction confirmed the presence of sodium acid urate monohydrate and identified hydroxyapatite and whitlockite in the accompanying dystrophic calcification of the aortic valves. Previous reports indicate that gouty tophi of the cardiac valves are rare: of the nine cases reported, eight occurred in the mitral valve.

Ein Gichttophus im Kiefergelenk und auf der Tuba Eustachii*

A 76-year old female patient was suffering from a right-sided conduction-type hearing loss due to a very painful tumour in the anterior parotid region. X-ray films showed a partial destruction of the right temporomandibular joint. Since the patient had undergone a left-sided mastectomy for breast carcinoma two years previously, an operation was performed under the suspicion of a metastatic lesion. A plum-sized gouty tophus was found adjacent to the temporomandibular joint. The head of the mandible was partly destroyed, the upper pole of the parotid gland displaced and atrophic. The dorsal and medial aspect of the tophus impinged on the cartilaginous portion of the Eustachian tube. In the postoperative course, the conduction-type deafness disappeared, the pain was relieved, and the mobility of the joint almost completely restored. To our knowledge this represents the second case of a gouty tophus in the temporomandibular joint, the first one where the size of the lesion resulted in impingement of the Eustachian tube and conduction-type deafness. It is noteworthy that the patient showed no other signs or symptoms of primary gouty arthritis.