Characterization of melamine-containing and calcium oxalate crystals in three dogs with suspected pet food-induced nephrotoxicosis.

The histomorphologic characteristics and chemical composition of the crystals associated with suspected pet food-induced nephrotoxicosis in 3 dogs are described. Kidney specimens from 2 dogs, a 3-year-old Parson Russell Terrier and a 3-year-old Bernese Mountain Dog, were examined. Both developed acute renal failure after eating canned pet food on the 2007 Menu Foods recall list. The third case was a kidney specimen from a 1-year-old mixed-breed dog from a similar 2004 outbreak of canine renal failure in Taiwan, which occurred after eating a commercial dog food. Hematoxylin and eosin (HE), 72-hour Oil Red O (ORO72h), Alizarin Red S (pH 4.1-4.3), and Von Kossa stains; infrared (IR) spectroscopy; and scanning electron microscopy with energy dispersive X-ray analysis (SEM/EDXA) were performed to determine the histomorphologic characteristics and chemical composition of the crystals observed in each case. Histomorphologic findings in each case included acute, marked tubular degeneration and necrosis with many intratubular birefringent crystals, and lymphoplasmacytic interstitial nephritis. In each case, most of the crystals were rough, pale brown, and stained with ORO72h but did not stain with Alizarin Red S (pH 4.1-4.3) or Von Kossa stains; these features were consistent with a plastic or lipid. IR spectroscopy and SEM/EDXA results were consistent with melamine-containing crystals. A second crystal type identified in each case was smooth and platelike with staining characteristics and IR spectroscopy and SEM/EDXA results consistent with calcium oxalate crystals. Melamine-containing crystals have distinct light microscopic, histochemical, and SEM/EDXA characteristics that facilitate their identification in tissue.

A fatality due to ingestion of hydrofluoric acid.

We report a fatal case of hydrofluoric acid (HF) ingestion with suicidal intent. Quantitation using an ion-selective electrode for fluoride in fresh bile, gastric contents, kidney, liver, skeletal muscle, urine, and vitreous humor yielded 6.5, 39.0, 10.0, 6.0, 4.5, 5.0, and 4.5 ppm, respectively. In addition to the unfixed specimens, fluoride ion was measured in the following fixed tissue: brain, heart, kidney, liver, pancreas, stomach, and heart. Tissues were measured directly and/or by using the technique of standard addition. Fluoride concentrations using either method were found to be comparable. Fluoride concentration in fresh tissue was consistent with toxicity, although the urine fluoride concentration was in the range observed for asymptomatic workers exposed to fluoride in air. Fixed tissue preparations revealed fluoride concentrations consistent with nonexposure, whereas examination of the formalin fixative revealed fluoride concentrations only slightly higher than negative control formalin. We conclude that fixed tissues are inappropriate for fluoride determination. This is the first case we are aware of that provides fluoride concentrations in skeletal muscle in a fatality involving HF ingestion.

The surgical pathology and cytopathology of US Persian Gulf War military veterans.

BACKGROUND: Tens of thousands of Persian Gulf War veterans (GWVs) have presented with medical symptoms since Operation Desert Shield and Operation Desert Storm. The Kuwait Registry at the Armed Forces Institute of Pathology was established to act as a repository for surgical pathology, cytopathology, and autopsy material from GWVs. OBJECTIVE: To identify conditions known to be endemic to the theater of operations in our cohort of GWVs. METHODS: The Kuwait Registry database was searched by computer for listed conditions endemic to the Persian Gulf region included in the registry through December 31, 1997. RESULTS: Of the 2582 patients in this cohort, 1 patient with hepatitis B and 15 patients with hepatitis C were identified. Other known endemic conditions of the Persian Gulf region were not found. CONCLUSIONS: Viral hepatitis (B and C), which is prevalent in the US population, was the only listed endemic condition identified in surgical pathology or cytopathology specimens in our cohort of GWVs.

Elemental analysis and clinical implications of calcification deposits associated with silicone breast implants.

Calcification of the fibrous capsule surrounding silicone breast implants is a well-recognized occurrence that increases with time following implantation. These mineralized deposits potentially confound mammographic breast cancer surveillance already made difficult by the obscuring effects of silicone breast implants. The authors performed elemental analysis of silicone breast implant-associated calcifications to define better their chemical composition as related to mammographic and clinical significance. Electron probe microanalysis and infrared spectroscopy revealed all of the calcification deposits to be calcium complexed with tribasic phosphate. No evidence of calcium oxalate, calcium carbonate, silicone, or talc was observed. Caution must be employed in interpreting mammograms in women with silicone breast implants as well as those who have had their silicone breast implants removed. High-density mammographic calcifications indicative of calcium phosphate associated with a silicone breast implant may represent an accepted consequence of implantation or nearby carcinoma. We recommend baseline mammography on women who have had their silicone breast implants removed to prevent unnecessary fine-needle aspiration or tissue biopsy of retained breast capsule calcifications during subsequent routine surveillance for carcinoma.

Characterization of silicone breast implant biopsies by Fourier transform infrared mapping.

Fourier transform infrared (FT-IR) spectral mapping was used to study polymers in human tissue associated with silicone breast implants. Biomaterials such as polyesters, polyurethanes and silicone were identified by FT-IR spectroscopy, and their relative locations and distributions within tissue specimens were characterized by three-dimensional (3D) spectral maps.

Fourier transform infrared and Raman microspectroscopy of materials in tissue.

Fourier transform infrared and Raman (FT-IR and FT-Raman) microspectroscopy were used to study materials found in human tissue. Individual cases involving cholesterol, calcium stearate, and a polystyrenesulfonate ion exchange resin demonstrate the utility of the spectroscopic data. Characteristic spectral bands for these materials were compared with those of authentic chemical species to confirm their identities. The role of vibrational spectroscopy in pathologic diagnoses is discussed.

Pathological and biophysical findings associated with silicone breast implants: a study of capsular tissues from 86 cases.

Breast implant capsular tissues from 86 cases were studied to characterize the relationship between capsular findings and the type of implant used. Tissues were examined by light microscopy, immunohistochemistry, scanning electron microscopy/energy dispersive x-ray analysis and Fourier transform infrared, and Raman microspectroscopy. Capsular pathology was influenced by the structure and composition of the implant. A pseudoepithelium at the inner capsular surface (synovial metaplasia) was noted with silicone gel-filled, saline-filled, and polyurethane-coated implants, and disproportionatelywith textured surface implants. Immunohistochemical studies of pseudoepithelium supported a macrophage/histiocyte cellular origin. Talc was identified intracellularly within macrophages in 42 cases. Capsular calcification was strongly associated with the presence of implant stabilization patch material. Infrared spectra were used to identify silicone, talc, Dacron, and two different types of polyurethane in capsular tissues. Micropapillary structures identified at the pseudoepithelial surface have, to the authors' knowledge, not been previously described.

Visualization of silicone gel in human breast tissue using new infrared imaging spectroscopy.

Between 1 and 2 million women in the United States have silicone breast implants. Complications include capsular contracture and calcification and possibly connective tissue diseases such as scleroderma and rheumatoid arthritis, a subject of some controversy. In order to accurately assess the role of silicone in any histopathologic change, it is necessary to confirm its presence and to identify other foreign materials in the capsular tissue. Although light microscopy is used to visualize regions of tissue containing foreign inclusions, their chemical identity can only be determined using analytical techniques such as infrared or Raman microscopy. However, these conventional microprobe techniques record spectra only at single points and require an a priori knowledge of the locations of the inclusion to be probed. To significantly extend the capabilities of both infrared spectroscopy and optical microscopy, we have developed a new infrared imaging system that completely integrates these two methods. In this manuscript we highlight the ability of the technique to screen rapidly and to determine accurately the presence, size and chemical composition of silicone gel inclusions in human breast tissue.

Sodium polystyrene sulfonate (kayexalate) aspiration: histologic appearance and infrared microspectrophotometric analysis of two cases.

OBJECTIVE: Sodium polystyrene sulfonate (kayexalate) is a cation-exchange resin given enterally for the treatment of hyperkalemia. Aspiration of this material is a rare occurrence, but when visualized in the alveolus, it has a characteristic microscopic appearance that is virtually diagnostic. In two cases, recognition of the characteristic morphology of the foreign material raised the question of sodium polystyrene sulfonate. DESIGN: We used infrared spectroscopy to demonstrate the presence of this material in lung biopsies of two patients by identifying foreign body particles. Histories of the patients were reviewed for exposure to sodium polystyrene sulfonate. SETTING: Two lung specimens were referred to the Armed Forces Institute of Pathology with an unknown foreign material identified within the air spaces. PATIENTS: The lung biopsies were from two children, one postterm female infant who died at 3 days of life and a 4-year-old girl who underwent lung biopsy during surgical repair for tetralogy of Fallot. Both patients had received sodium polystyrene sulfonate previously for control of hyperkalemia. RESULTS: The lung specimens showed characteristic basophilic, amorphous foreign material in airspaces on histologic sections. The identity of this material was confirmed by Fourier transform infrared microspectrophotometry. CONCLUSIONS: To our knowledge, we report the first two cases of sodium polystyrene sulfonate aspiration in children. This material has a distinctive morphologic appearance on histologic sections, and its identity can be confirmed by Fourier transform infrared microspectrophotometry.

Raman chemical imaging: histopathology of inclusions in human breast tissue.

High-definition Raman chemical imaging microscopy is applied to the histopathological characterization of biopsied human breast tissue containing foreign polymer inclusions. The polymer material is found in a patient with a history of silicone implant breast reconstructive surgery. Silicone implants are, on occasion, anchored to the soft tissues of the chest with polyester patches. In the case studied here, the polyester anchors were incorporated into the patient's fibrous tissue surrounding the implant. High-definition Raman chemical imaging provides molecular-specific image contrast in the complex breast tissue matrix without the use of stains or dyes. This is the first example in which Raman spectroscopic imaging microscopy has been applied to pathology. A goal of this and future studies is to complement traditional histopathologic diagnoses of disease states utilizing vibrational spectroscopic imaging techniques.

Assessment of the histopathological lesions and chemical analysis of feral cats to the smoke from the Kuwait oil fires.

Twenty-six adult or subadult feral cats were collected from Kuwait approximately 8 months after the ignition of the Kuwait oil wells. These animals were obtained from two sources: 12 animals from Kuwait City, a relatively smoke-free area, and 14 from the city of Ahmadi, an area with heavy smoke. Animals were euthanized and a complete set of tissues consisting of all major organs was taken for histopathology. Samples of lung, liver, kidney, urine, and blood were also taken for toxicology. Histopathological lesions observed in the lung were mild accumulations of anthracotic pigment in the lungs of 17 cats. Hyperplasia of the bronchial and bronchiolar gland in 8 cats, and smooth muscle hyperplasia of bronchioles in 14 cats. Tracheal gland hyperplasia was observed in 7 cats, and minimal squamous metaplasia of the tracheal mucosa in 17 cats, Laryngeal lesions consisted of submucosal gland hyperplasia in 2 cats and squamous metaplasia of the mucosa in 5 cats. Hyperplasia of the nasal submucosal glands was observed in 6 animals. The pharyngeal mucosa as well as other organs and organ systems were normal in all cats. Atomic absorption analysis for 11 metals was performed; vanadium and nickel levels (two metals that were present in the smoke from the oil fires) are not indicative of substantial exposure to the oil fires. Based on the histopathological findings and toxicological analysis, it is felt that inhalation of air contaminated with smoke from the oil fires had little or no long-term effect on the animals examined.

Fourier transform infrared microscopic identification of foreign materials in tissue sections.

Fourier-transform infrared microspectroscopy was used to identify polymeric microparticles, such as polyethylene, polysulfone, polytetrafluoroethylene, polyurethane, silicon-based, and nylon-based plastics, in tissue sections. Foreign particles as small as 30 microns in diameter were identified. In addition to being a nondestructive technique, infrared microscopy allows for more precise structural identification of polymeric materials than do X-ray or scanning electron microscopy.