Effects of clinical service reorganisation on cellular pathology workload

AIMS

To assess changes in volume and complexity of cellular pathology workload after clinical service reorganisation and alterations in pathology reporting practices, and to identify objective measures of change applicable to all cellular pathology departments. The ear, nose, and throat (ENT), head and neck (HN) specialty was chosen for assessment.

METHODS

Cellular pathology workload from the ENT-HN surgical specialty was assessed numerically and the complexity in examination of cancer resection specimens was evaluated. Medical and technical time inputs in the reporting of ENT-HN cancer resections were measured prospectively, and the histological and cytological workload arising from the management of such cases was obtained.

RESULTS

The 88.83% increase in ENT-HN specimens contrasted with a 13.53% increase in total surgical workload. Substantial increases in work complexity were found when measured as blocks/slides for each case and number of histochemical/immunohistochemical requests. On average, examination of one ENT-HN cancer case consumed 55% of one pathologist's work session and over one 10th of a technician's working week. On average, each cancer generated 3.3 histological and 1.06 cytological specimens.

CONCLUSIONS

Evidence is provided of the increase in cellular pathology workload and in its complexity. This study lists objective measures of complexity applicable to all pathology subspecialties. Given the workforce crisis and expanding clinical needs, realistic workload calculations should include measurement of complexity and not just volumes.

The use of histological techniques for the demonstration of ion exchange resins

AIM

To establish the staining characteristics of certain ion exchange resins in histological material, with a view to enabling confident differential identification.

METHODS

Various histological staining procedures were applied to selected pathological material and prepared agar blocks containing the cation exchange resin calcium polystyrene sulphonate and the anion exchange resin cholestyramine.

RESULTS

Calcium polystyrene sulphonate uniquely stained strongly by a direct Schiff's reagent procedure without any preoxidation and by the Ziehl-Neelsen method. Cholestyramine was negative by the former method but stained strongly with a standard Congo red technique.

CONCLUSIONS

These staining results are consistent with the known structure and properties of polystyrene sulphonate and cholestyramine resins. Polystyrene sulphonate resins have the virtually pathognomonic feature of direct Schiff positivity, while morphology, location, and strong non-birefringent Congo red positivity facilitate the identification of cholestyramine. It is possible that the intrinsic staining characteristics of cholestyramine may be lost once it has bound to its target.

Subcutaneous deposition of beta 2-microglobulin amyloid in a long-term haemodialysis patient

Subcutaneous deposition of beta 2-microglobulin (beta 2-M) amyloid is an uncommon finding in uraemic patients on long-term haemodialysis. A 60-year-old female on haemodialysis for 16 years developed a subcutaneous haematoma 2 years prior to death. At necropsy the lesion contained numerous deposits of beta 2-M amyloid as well as evidence of old haemorrhage, fibrous repair, dystrophic calcification and calcium oxalate crystal deposition. Highly sulphated glycosaminoglycans were present in the amyloid deposits. beta 2-M amyloid deposits were also present in the hip joint, cervical and lumbar spine, and in small blood vessels of the heart, liver, and lung. The possible role of trauma and tissue glycosaminoglycans changes in the formation of subcutaneous amyloid tumours is discussed.

Use of betapropiolactone to disinfect fresh tissue without impairing antigenicity: method applicable to human immunodeficiency virus (HIV) positive tissue

A method for inactivating viruses in tissues is reported that does not impair the antigenicity of the Coxsackie virus or of some common tissue antigens, a common problem with standard tissue fixation methods. Tissues can be placed briefly in Betapropiolactone before cryostat sectioning without any adverse effect on preservation or antigen expression. It is suggested that use of Betapropiolactone is applicable to tissues harbouring or exposed to the human immunodeficiency virus (HIV). As betapropiolactone has been reported to be carcinogenic in rodents any potential danger can be avoided by basic simple precautions.

Chrysiasis: transmission electron microscopy, laser microprobe mass spectrometry and epipolarized light as adjuncts to diagnosis

Two patients receiving gold therapy for rheumatoid arthritis developed skin pigmentation, chrysiasis, which in one appeared 4 months after cessation of the therapy. The diagnosis was confirmed by transmission electron microscopy and mass spectrometry laser microprobe analysis of paraffin sections and its extent demonstrated by epipolarized light. The condition is poorly reported and clinically may be confused with silver and mercury impregnation. Tissue diagnosis requires ancillary methods and of these, transmission electron microscopy and laser microprobe mass spectrometry are excellent examples. The transmission electron microscopy findings differ from previous reports and raise doubts on the hypothesis on the role of the skin in gold excretion. Because of the renewed interest in crysotherapy and the latent period that can separate this from chrysiasis, an increase in chrysiasis and the need for its diagnosis can be anticipated.

Emericella nidulans in a maxillary sinus fungal mass

Sexual reproductive stages of fungi are very rarely found within mammalian tissues. We report here coexistence of cleistothecia associated with Emericella nidulans and its conidial state, Aspergillus nidulans, in a fungal mass which developed in a maxillary sinus.

Factor VIII related antigen positive macrophages and acquired immune deficiency syndrome (AIDS): a problem of antibody specificity

A further histopathological complication of atypical mycobacterial infection in acquired immune deficiency syndrome (AIDS) is reported. Positive reactivity between mycobacterial antibodies within a polyclonal antiserum and mycobacteria within tissues resulted in false positivity with this reagent to factor VIII related antigen. This complication may be avoided either by prior testing of the antiserum, or by purification, or by the use of monoclonal antibodies. Histopathologists examining tissues from patients with AIDS and those with disseminated mycobacterial infections and using immunohistochemical techniques should be aware of this occurrence.

Tannic acid in histology: an historical perspective

The development of tannic acid as a reagent in histological methods is traced against a background of widespread use in science and technology from times of antiquity. Numerous light microscopic methods involving tannic acid, particularly in conjunction with iron and silver, have been described for a variety of tissue components. In most applications, tannic acid functions as a mordant. Current use is generally restricted to methods based on its affinity for collagen. The most significant histological use of tannic acid in contemporary times is as an adjunct to conventional glutaraldehyde-osmium-heavy metal fixation and staining for ultrastructural studies of tissue structures not normally clearly demonstrated. Tannic acid reacts with various components by mechanisms which are often not fully understood.

Polystyrene sulphonates and aspiration pneumonia: a histochemical study

The histochemical characteristics of a sulphonated polystyrene resin were investigated and compared with those of sulphonic acid residues derived from intrinsic tissue components. The major features of the resin particles were their direct Schiff positivity and basophilia. Unlike the tissue sulphonic acids, the resin particles failed to stain with alcian blue. Because of their acid nature, the particles may be responsible for the onset of an aspiration pneumonia if they are accidentally inhaled by debilitated patients.

Tyrosine-rich crystals in pleomorphic adenomas of parotid glands

Histochemical methods for proteins were applied to crystals found in pleomorphic adenomas of the parotid. Positive reactions were obtained with methods for tyrosine, tryptophan, arginine and sulphydryl groups, and indicate a greater complexity of composition than has previously been acknowledged.

Infiltration of the supraorbital nerve by basal cell carcinoma

A case report is presented of a man with a recurrence of a basal cell carcinoma on the forehead that upon histologic examination of the specimen of surgical excision revealed both perineurial and endoneurial invasion of several fascicles of the supraorbital nerve by neoplastic cells.

Observations on the histochemistry of barium

The histochemistry of barium was investigated with particular reference to the use of sodium rhodizonate. It was found that not all batches of sodium rhodizonate were able to effect satisfactory visualisation of barium deposits. None of the other histological parameters considered gave a consistent indication of the presence of barium.

The use of a laser microprobe to identify calcium oxalate in histological material

Some birefringent renal deposits were found to give the usual histological reactions for calcium oxalate but were soluble in caustic alkalis. Comparison with known oxalate crystals using a laser microprobe mass analyser confirmed the presence of calcium oxalate. Similar crystals were found in liver tissue from a rat poisoned with ethylene glycol.

Splenic infarction and tissue accumulation of crystals associated with the use of clofazimine (Lamprene; B663) in the treatment of pyoderma gangrenosum

A male patient 68 years, suffering from pyoderma gangrenosum which was resistant to conventional treatment, received clofazimine 400 mg daily for 5 months, then reducing to 300 mg daily for the next 6 months. Eleven months after starting the drug, he was admitted to hospital with severe abdominal pain, laparotomy revealing infarction of the spleen, with violaceous congestion of the small bowel. The spleen was removed and post-operative recovery was satisfactory. Histopathological examination of the spleen (removed at operation) and of tissue from a duodenal biopsy (taken postoperatively) showed large numbers of striations and outlines suggestive of crystal deposition. Mesenteric lymph node revealed a massive accumulation of crystals in cortical and medullary sinuses. The findings emphasize that clofazamine should not be used in high dosage over prolonged periods of time, except under close clinical and laboratory supervision, and for conditions not amenable to other drugs.

Histopathological occurrence and characterisation of calcium oxalate: a review

Oxalosis is the histological manifestation of a number of diverse clinicopathological states involving abnormalities of both endogenous and exogenous oxalate. Crystalline deposits of calcium oxalate, usually first detected by their birefringence, may be characterised by a combination of their physical and tinctorial properties.

An evaluation of some complexing methods for the histochemistry of calcium

A selection of reagents capable of complexing with calcium in various ways was compared by applying them to tissue sections known to contain calcium in a variety of physiochemical states. Their histochemical potential was evaluated according to their sensitivity, specificity, accuracy of localisation and intensity of staining. Murexide, for light microscopy, and 8-hydroxyquinoline, for fluorescence microscopy proved to be the best overall reagents. They failed to demonstrate calcium oxalate, which was well shown by naphthalhydroxamic acid.

The histochemical demonstration of calcium with 8-hydroxyquinoline

A method for the histochemical demonstration of calcium using 8-hydroxyquinoline was investigated. It was found to give intense, highly selective staining of various pathologic and natural calcifications, and compared favourably with conventional procedures for calcium. Calcium oxalate and calcium pyrophosphate were not stained.

Calcium pyrophosphate. Histological characterization of crystals in pseudogout

Deposits taken from an acetabulum and the head of a femur and known to contain crystals of calcium pyrophosphate were examined by selected histological methods for calcium after the application of a variety of solvents. Treatment with 10% ferric chloride removed all calcium salts tested, except a birefringent crystalline component in the pyrophosphate deposits. This corresponds to the previous optical and morphological descriptions of calcium pyrophosphate as found in synovial fluids. Calcium pyrophosphate stains consistently only by the fluorescent morin method.

Calcium oxalate and the von Kossa method with reference to the influence of citric acid

Crystals of calcium oxalate in pathological material and artificially precipitated in the absence or presence of citric acid in gelatin models were examined by polarized light and treated with silver nitrate under a variety of conditions. It was found that the intensity of the staining reaction was largely proportional to the strength of the silver solution, and was enhanced in in vitro studies by the presence of citric acid. Staining was also influenced by the crystal form, which was itself related to the absence or presence of citric acid.

Calcium polystyrene sulphonate: an unusual cause of inhalation pneumonia

Images