POLY MYOSITIS

9.

10.

cluding Systemic Lupus Erythematosus, Polyarteritis, 1 I .

ton, 1956, p 232 12.

Dermatomyositis, Systemic Scleroderma, Thrombotic Thrombocytopenic Purpura. New York, Grune & Strat-

O’Leary PA, Waisman M: Dermatomyositis: a study of forty cases. Arch Dermatol41: 1001-1019, 1940 Eaton LM: The perspective of neurology in regard to polymyositis: a study of 41 cases. Neurology (Minneap) 4:245-263, 1954

13.

247

Logan RG, Bandera JM, Mikkelsen WM, et al: Poly- myositis: a clinical study. Ann Intern Med 65:996-1007, I966 Bohan A, Peter JB: Polymyositis and dermatomyositis. I. N Engl J Med 292:344-347, 1975 Sharp GC, Irvin WS, LaRoque RL, et al: Association of autoantibodies to different nuclear antigens with clinical patterns of rheumatic ,diseases and responsiveness to ther- apy. J Clin Invest 50:350-359, 1971

DISCUSSION MICHAEL D. LOCKSHIN

The patients described by Bunch, O’Duffy, and McLeod clearly illustrate how humbling the practice of rheumatology can be.

The interest of their communication lies in its description of a particular type of hand deformity in patients with polymyositis. But from the case reports it appears obvious that other equally experienced clini- cians might have diagnosed these patients as having myositis secondary to systemic lupus erythematosus (SLE) (positive antinuclear antibody and LE cell tests) or progressive systemic sclerosis (PSS) (calcinosis and terminal digit resorption). There is nothing unique about the authors’ findings if either of these alternate diagnoses is accepted, because severe myositis, although uncommon, may be found in either disease; in SLE both calcinosis ( I ,2) and thumb hyperextension-subluxation (2,3) have been well described in the past. The DIP erosions depicted in Figure 3 are common and nonspecific.

The authors’ use of the ARA criteria to rule out SLE must be regarded as irrelevant. The ARA criteria were devised to assure homogeneity of large patient populations for comparison of prognosis and therapy and not to invalidate an otherwise acceptable diagnosis

From the Hospital for Special Surgery and the New York Hospital-Cornell University Medical College, New York, New York.

Michael D. Lockshin, M.D.: Assistant Professor o f Medi- cine.

Address reprint requests to Michael D. Lockshin, M.D. , Hospital for Special Surgery, 535 East 70th Street, New York, New York 10021.

in an individual patient. For instance a young woman with arthralgia, fever, microscopic hematuria, anti- DNA antibodies, hypocomplementemia, and biopsy- proved lupus nephritis fulfills no ARA criterion but certainly has SLE. In the experience of Fries and Siege1 (4) only half the patients diagnosed as having SLE ful- filled ARA criteria at their first visit.

The problem of differential diagnosis is really one of specificity and weighting of individual criteria. From the clinician’s point of view the characteristic facial rash, clinical or pathologic evidence of lupus nephritis, and high titer antinuclear antibody or anti-DNA antibody weigh far more heavily in the diagnosis of SLE than do other criteria. Similarly muscle calcification and the typ- ical rash about the eyes, neck, and hands strongly aid the diagnosis of poly-dermatomyositis; cutaneous scle- rosis (other than sclerodactyly), typical gastrointestinal dysmotility or diverticula, and acute hypertensive renal failure are nearly specific for PSS.

I n the absence of these typical features, personal taste in diagnosis becomes the overriding characteristic in classifying individual patients. I myself have had the frustration of seeing a patient of mine with PSS (acro- sclerosis, Raynaud’s phenomenon, and scleroderma kid- ney) published by our neurologic staff as a case of polymyositis (coexistent myositis). And a patient with SLE has been entered into our hospital records as hav- ing rheumatoid arthritis because the autopsy prosector was more impressed with her nonerosive hand defor- mities than with her anti-DNA antibody.

Arthritis and Rheumatism, Vol. 19, No. 2 (March-April 1976)

248 BUNCH ET AL

The same reasoning about personal tastes in di- agnostic criteria can be applied to the cases of Bunch, O’Duffy, and McLeod. Renal findings and anti-DNA antibody are not mentioned, nor is it clear whether Patient 4, with terminal digit resorption, also had Ray- naud’s phenomenon. The only rash mentioned is that of Patient 6 , which by description may be accepted as dermatomyositis. It is therefore presumptive that lupus rash, other dermatomyositis rash, nephritis, and anti- DNA antibodies were absent. Unfortunately there is no spec@ criterion for diagnosis of poly-dermatomyositis other than the rash because the inflammatory myositis of both SLE and PSS is similar to that of polymyositis in clinical, enzymologic, pathologic and electro- myographic characteristics.

The message of the report by Bunch, O’Duffy, and McLeod is thus reduced to the fact that a hand deformity (which is seen in SLE) and calcinosis (like that seen in PSS) are present in some patients with inflammatory myositis, positive antinuclear antibody tests, and occasional positive LE cell tests. The diagnosis of polymyositis in these patients must therefore be qual- ified by the understanding that it is the authors’ opinion that the term “polymyositis” represents a diagnosis rather than a partial description.

Should terms like “overlap syndrome,” “sclero- dermatomyositis,” “mixed connective tissue disease,” and “undifferentiated connective tissue disease” be

AUTHORS’ REPLY

We appreciate Doctor Lockshin’s thoughtful comments. However the main thrust of our paper is to describe an unusual arthropathy limited to the hands in a group of patients who had polymyositis but did not have clinically recognizable rheumatoid arthritis, sys- temic lupus erythematosus, or scleroderma. Although we agree with Doctor Lockshin’s misgivings about ap- plying such criteria in everyday practice, we anticipated taxonomic difficulties in accepting our patients as hav- ing polymyositis by including ARA criteria to provide the reader a clearer picture of the type of patient we were describing. The terminal digit resorption in Case 4 was secondary to trauma. All of these patients had soft skin with no other features clearly indicating scleroderma.

used for such patients? From a clinical point of view the terms are useful reminders to the physician to anticipate complications of all syndromes under treatment rather than only those of the predominant syndrome. From a prognostic point of view i t may be possible to define a subset of patients that differs from the more classic group of patients. From a didactic point of view such terms should inspire humility in the physician who is unable to define clearly the diseases with which he or she is concerned. But it may well be that the greatest impor- tance of awareness of these undifferentiated patients is that they serve as intellectual prods to the understanding by recalling that neat clinical distinctions are probably not separate diseases but rather represent variations (possibly genetic) of individual patients’ responses to as yet undefined etiologic agents.

REFERENCES I . Kabir DI, Malkinson FD: Lupus erythematosus and calci-

nosis cutis. Arch Dermatol 100: 17-22, 1969 2. Bleifeld CJ, Inglis AE: The hand in systemic lupus er-

ythematosus. J Bone Joint Surg 56A:1207-1215, 1974 3. Aptekar RG, Lawless OJ, Decker JL: Deforming non-

erosive ar thr i t is of t h e hand in systemic lupus erythematosus. Clin Orthop 100: 120-124, 1974

4. Fries JF , Siege1 RC: Testing the “preliminary criteria for classification of SLE.” Ann Rheum Dis 32:171-177, 1973

Anti-n DNA antibody tests were not done. None of the patients had nephritis. Urinalyses and creatinines were normal.

We have never seen this unusual type of arthropathy limited to the hands in the clinical setting described here without a chronic mild polymyositis. Therefore the finding of this type of hand arthropathy in the absence of systemic lupus erythematosus, scleroderma, or rheumatoid arthritis may be an impor- tant clinical clue to the diagnosis of an unsuspected polymyositis. We do not feel that our cases solve the complex problems of the “overlap” syndrome.

THOMAS W. BUNCH, M.D. J. D. O’DUFFY, M.D. RICHARD A. MCLEOD, M.D.