Report of Participants’ Meeting held
at
as part of
the meeting of the
Over 20 members of the Scheme were present. The meeting was
also attended by Professor Agnes Fogo, from
The original breakdown of proffered diagnoses, before amendment as described below, is available on the scheme website at http://www.le.ac.uk/pa/pnf1/eqa/ along with all the images displayed during the case discussion at the Participants’ Meeting.
Professor Furness opened the meeting with a reminder of the need to review each case for its suitability for personal scoring in the EQA scheme, and to make decisions on how each suitable case should be used for scoring. He also pointed out that the meeting should be used as a forum to discuss any management issues relating to the scheme.
This was a case of thrombotic microangiopathy which could reasonably be attributed to malignant hypertension, as that condition was clearly identified in the clinical information. Glomerular changes were present and the material circulated did not include immunohistochemistry or electron microscopy so it was regarded as appropriate to suggest that underlying glomerulonephritis still needed to be excluded. (Diagnoses 1, 2, 3 and 6 were therefore to be merged and all regarded as correct).
The meeting agreed that the material circulated, though less than ideal, was sufficient for personal scoring despite several participants having complained about inadequate material. There was a discussion over what to do about one participant who had refused to offer a diagnosis. The Organiser argued that if this response was accepted with no penalty, in a case which the Meeting had agreed to use for personal scoring, it might encourage a large number of such responses in the future, which would be undesirable. After discussion it was agreed that on this occasion half marks should be awarded to the participant who had refused to offer a diagnosis, but that in future participants should be reminded to make as much as they can of the material available, and register concerns about adequacy at the bottom of the response form so that this question can be considered by the Participants’ Meeting.
This was a case of post-infective / endocapillary proliferative glomerulonephritis, although it was never confirmed by ASOT. Subsequent EM was reported by the submitting pathologist to support the LM diagnosis.
The meeting discussed how to handle the diagnostic category ‘Mesangiocapillary Gn – post-infectious’. It was decided that this clearly indicated that the diagnosis was not idiopathic mesangiocapillary Gn. Furthermore, the underlying pathogenetic process was correctly identified, and it was agreed that post-infectious Gn may produce some mesangiocapillary features as well as endocapillary proliferation. This diagnosis was therefore regarded as acceptable and will be merged with the consensus diagnosis as ‘post-infectious glomerulonephritis’.
There was some discussion of whether this should be recorded as IgA nephropathy, Henoch-Schönlein purpura, or both. Some argued that in view of the clinical history of purpuric rash, ‘IgA nephropathy’ was incorrect. Others argued that from a pathologist’s viewpoint we should admit that the two are indistinguishable. It was agreed to merge all diagnostic categories including IgA nephropathy or HSP. Other diagnoses were regarded as incorrect.
This was a necrotising pauci-immune glomerulonephritis, indicating a vasculitic process.
There was some discussion as to whether specific diagnoses of ‘microscopic polyangiitis’ or ‘Wegener’s granulomatosis’ were justified on the basis of the material available. It was argued that on the histological appearances alone the two cannot be reliably distinguished, and ‘sinusitis’ is too common a symptom in the population to be taken as conclusive evidence of Wegener’s. However it was agreed that all proffered diagnoses would be merged and regarded as correct.
It was agreed that in this case it might have been more interesting to grade activity and chronicity, but that there is no single agreed method to do this. It was suggested that in the future participants who are contemplating submitting a case with an obvious diagnosis such as this might consider stating the diagnosis in the clinical information and inviting assessment of ‘grade and stage’ rather than diagnosis as the assessed EQA activity. In this case it was agreed that the submitting pathologist would have to indicate a specific grading system.
This was a case of membranous glomerulonephritis. Many participants, noting some glomerular hypercellularity, had commented on the need to exclude SLE. However, it was agreed that to attribute the process to a definite diagnosis of SLE was wrong and potentially misleading. The immunohistochemistry showed a convincing absence of the mesangial immunoglobulin deposits which would be typically expected in lupus nephritis. Serology subsequently proved negative. It was therefore agreed that ‘Membranous Gn due to SLE’ (my emphasis) should be regarded as incorrect.
This was a case for education and interest, not personal scoring. The submitting pathologist was present for the discussion. He had initially shared the view of many participants that HIV should be considered, despite the negative serology. However in view of the subsequent course the local clinico-pathological view was that the process was all a consequence of malaria.
Professor Fogo asked about drug history, pointing out that appearances such as these could be caused by some drugs, notably palmidronate. The submitting pathologist was not aware of any history of exposure to such a drug.
The agreed diagnosis was interstitial nephritis. It was agreed that most of the diagnostic categories which included interstitial nephritis would be regarded as correct. However, ‘interstitial nephritis due to chronic pyelonephritis’ was judged to be wrong, as the section did not contain evidence of pyelonephritic scarring and if given as a confident diagnosis this was likely to be misleading. Similarly ‘chronic interstitial nephritis’ was regarded as, as a minimum, misleading. Despite only having a H&E section, participants agreed that there was no convincing evidence of interstitial fibrosis, so this would he awarded only half marks.
Many participants had noted fragmented intratubular casts, and suggested the need to exclude myeloma. However, the few participants who made a confident diagnosis of myeloma on the basis of the material provided were judged to be wrong.
The clinical information in this case stated a ‘confident clinical diagnosis of scleroderma’. Hypertension was also present. The consensus diagnosis was that the biopsy changes were attributable to the scleroderma.
A discussion ensued on the acceptability of the other proffered diagnoses. After a vote it was agreed that ‘small vessel vasculopathy’ was insufficiently specific; not only did it not mention scleroderma, ‘vasculopathy’ could be acute or chronic and could infer many different processes. This was awarded half marks. Similarly ‘vasculopathy secondary to hypertension’ was judged to be wrong as the cause was believed to be scleroderma / systemic sclerosis.
This was a pauci-immune necrotising vasculitis. The material available did not permit a confident distinction between types of vasculitis. It was agreed that all proffered diagnoses would be merged.
This was a crescentic glomerulonephritis. Many participants had complained about the absence of any information about immunohistochemistry or electron microscopy – the fact that it was ‘pauci-immune’ was stated in the follow-up information but had been withheld from participants. Furthermore the information provided was vague about the timescale of events post-partum. Consequently an unusually high number had recommended that the case should not be used for personal scoring.
Most participants had proffered ‘crescentic glomerulonephritis NOS’, but some had made valiant attempts, of varying plausibility, to suggest a cause. Dr Griffiths pointed out that this case did not have the appearance of post-partum thrombotic microangiopathy. ‘Regenerating ATN’ was clearly wrong. Some participants at the meeting suggested that attempting to proffer a diagnosis more specific than was justified by the material available was wrong and should be penalised. A vote was held on whether the case should be used for personal scoring, and an even split of 11 to 11 resulted. The Organiser used his casting vote to delete the case, swayed by the large number of participants who had recorded objections on their response forms.
The preferred diagnostic category was Goodpasture’s syndrome or disease. The Organiser had already merged these two terms under the term Goodpasture’s syndrome.
Professor Fogo said that her institution had been the workplace of Dr Goodpasture. She pointed out that this should be recorded as Goodpasture’s disease, not syndrome, as there was no record of lung involvement to justify the use of the word ‘syndrome’. Furthermore, the man himself would have preferred it to be called ‘anti-GBM crescentic glomerulonephritis’. The Organiser confessed himself at fault.
An enquiry as to whether the apostrophe-s should be omitted did not result in a definite conclusion.
Professor Fogo informed the meeting that ‘Crescentic glomerulonephritis type 1’ is an old and little-used term for anti-GBM glomerulonephritis, so the meeting agreed this should be regarded as correct, if idiosyncratic. ‘Crescentic glomerulonephrtis NOS’ was regarded as insufficiently specific in this case and therefore wrong.
This was a truly bizarre biopsy, included for interest and not for personal scoring. All responses have therefore been deleted. The follow-up information provided by the participant who submitted the case was noted, together with the suggested diagnosis of POEMS syndrome (Polyneuropathy, Organomegaly, Endocrinopathy, Monoclonal protein, Skin changes) but without the monoclonal protein. The Organiser suggested a reference which may be relevant; Machiguchi T, Yoshida H, Tamura T. Macrophage and platelet-infiltrated glomerulonephritis with interstitial angiofollicular hyperplasia in a patient with POEMS syndrome. Nephrol Dial Transplant. 2001;16:2270-1
However, the final diagnosis remains uncertain.
Peter Furness
Renal EQA Scheme Organiser