61
Conferences & Reviews
Painful Subacute Thyroiditis in Hawaii ROBERT A. NORDYKE, MD; FRED I. GILBERT, Jr, MD; and CHRIS LEW, MD, Honolulu, Hawaii
Between 1960 and 1982 we prospectively studied 269 patients with painful subacute thyroiditis to determine the demographic characteristics, seasonality, and natural course of the disease. The mean age for all patients was 37.1 years. The female:male ratio was 6.7:1. At the first visit, disease was bilateral in 690/o. No epidemic or seasonal pattern was identified. The mean duration of thyroid tenderness was 2.2 months and that of palpable thyroid lumps was 2.8 months. This time difference, sometimes lasting many months, left a painfree "window" during which the palpable hard residual mass of subacute thyroiditis may be confused with other thyroid problems, especially cancer. (Nordyke RA, Gilbert Fl Jr, Lew C: Painful subacute thyroiditis in Hawaii. West J Med 1991 Jul; 155:61-63)
Subacute (de Quervain's) thyroiditis is an inflammatory condition of the thyroid probably caused by a virus, with a possible genetic predisposition."2 It can be localized or generalized, mild or severe, lasting weeks to many months. At different stages it may be confused with a "sore throat," the hyperthyroidism of Graves' disease, thyroid cancer, or bleeding into a cyst. Various authors report a female:male ratio of 3:1 to 7:1 and a peak incidence between 40 and 50 years of age.3`6 Based on the number of patients seen at major hospitals, the incidence of the disease has been hypothesized to be higher on the West Coast of the United States compared to the East,'-8 but this has been questioned.9 The incidence appears to be highly variable worldwide.8'0"' Some studies have reported a significant increase during the summer months,3.4"12 and others have found no seasonal trend.6'9 Excellent general reviews of subacute thyroiditis are available. 1"1l We examined the demographic characteristics (age, sex, and race) and the seasonal occurrence of disease of 269 patients with painful subacute thyroiditis seen at Straub Clinic in Hawaii. In addition, the clinical course of 70 patients was studied with special attention to the painfree "window" the time between the cessation of tenderness and the disappearance of palpable thyroid abnormalities attributable to thyroiditis. Patients seen for the first time during this window are likely to be misdiagnosed because tenderness is absent and the gland often feels unusually hard and irregular. Patients and Methods Study Population This study included all patients referred to the thyroid clinic of Straub Clinic in Honolulu between 1960 and 1982 who were diagnosed with painful subacute thyroiditis. Some patients were referred by outer-island physicians, but most were sent to us by Straub Clinic physicians (ranging from 36 in 1960 to 105 in 1982). During that time, Straub was entirely a fee-for-service facility, caring for about 15% of the civilian population of the island of Oahu. All patients had thyroid gland tenderness at their first visit or by recent history (we excluded patients falling into the
more recently described nontender variants""2). There were 269 such cases. Of these, 70 were observed through the course of their disease.
Patient Examination Clinical examination was similar in all patients, using a standardized work sheet II that contained the referral source, reason for the referral, demographic information (age, sex, and race), chief complaint, present illness, history of thyroid disease, physical findings related to the thyroid, clinical impression, and final diagnosis after all data became available. The diagnosis was made on the basis of typical signs and symptoms, including tenderness corresponding to a palpable mass, with pain often radiating to the ipsilateral jaw and ear, and clinical follow-up. When needed for confirmation, laboratory tests were obtained, including serum thyroxine estimates, iodine 131 thyroidal uptake at 6 or 24 hours, erythrocyte sedimentation rate, and thyroid scan. On the first visit, special attention was given to the time symptoms began, severity of symptoms, the initial location of pain and tenderness, thyroid gland size and palpation characteristics, and anatomic areas of tenderness and enlargement (localized, unilateral nonlocalized, or bilateral). On follow-up visits, special attention was given to gland size, palpable enlargements, tenderness, the correspondence of enlargements and tenderness, the migration of findings, and the time of the disappearance of tenderness and palpable abnormalities.
Results Demographic Characteristics Among the 269 patients, 47% were white, 24% Japanese, and the rest were various other races. The white:Japanese ratio was 2:1. This ratio is 1.8:1 for all of Straub Clinic's patients. The mean age was 37.1 years with a range from 4 to 86. Most cases (77%) occurred between ages 20 and 49 (Figure 1). The age distribution for male and female patients was similar. Female cases predominated at all ages, accounting for 87% of the 269 cases and giving a female:male ratio of 6.7:1. Among the 70 patients observed through the course of their illness, women predominated by a ratio of 6.1:1; 46%
From the Department of Nuclear Medicine, Straub Clinic & Hospital (Drs Nordyke and Gilbert), and the Department of Medicine, University of Hawaii John A. Burns School of Medicine (Drs Nordyke, Gilbert, and Lew), Honolulu, Hawaii. Grant support for this project was provided by the George F. Straub Trust and the Pacific Health Research Institute, Honolulu, Hawaii. Reprint requests to Robert A. Nordyke, MD, Straub Clinic & Hospital, 888 S King St, Honolulu, HI 96813.
SUBACUTE THYROIDITIS IN HAWAII
62 10-
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1 10
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/
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10-19 20-29 30-39 40-49 50-59 60-69 70-79 80-89 Age, years Figure 1.-The graph depicts the age distribution by decade of 269 patients with painful subacute thyroiditis. 0-9
were white and 27% were Japanese. The mean age for female patients was 41.1 years with a range of 11 to 80.
Seasonal Variation The distribution of cases diagnosed in each month throughout the year is presented in Figure 2. There was no summer peak, in contrast to the findings of some reports.3'4" 2 The only apparent trend, a lower percentage of cases in April through August compared with September through March, was not statistically significant. The one exception to this trend was the low incidence in December.
Localization Within the Thyroid Gland When cases were categorized by area of the gland involved on the first visit, the area was discretely localized in 16%, nonlocalized but unilateral in 15%, and bilateral-usually diffuse, and including those that had migrated by the time of the first observation-in 69%. All three categories of involvement were more common in white patients than in Japanese. Duration of Tenderness and Palpable Lumps The progress of tenderness and palpable lumps was observed for 70 patients throughout the course of their disease. The time symptoms began was estimated by history obtained at the first visit. Tenderness and palpable lumps disappeared
at about the same time in 50 patients (72%), and in the other 20 patients (28%) tenderness ceased first, leaving areas of firm or hard lumps that disappeared later. The duration of tenderness for the entire group was 65.4 + 42.5 days (mean + standard deviation). The duration of palpable abnormalities that later disappeared spontaneously was 83.5 ± 51.5 days. Two patients had prolonged, severe, debilitating pain and tenderness poorly responsive to treatment with prednisone. One had a near-total thyroidectomy and the other an ablative dose of sodium iodide 1 131. Both became free of pain and tenderness after their definitive treatment. The percentages of patients with pain and palpable abnormalities at various times after the disease occurred are given in Figure 3, which illustrates the magnitude of the painfree window. More patients continued to have palpable abnormalities than persistent pain at any given duration of follow-up. The figure also shows the broad range of durations of pain and palpable lumps. Some patients were symptomfree within a week or two; for others, pain and palpable irregularities persisted for months.
Discussion The diagnosis of painful subacute thyroiditis can usually be made on clinical grounds alone. In nearly all instances, its course is benign and self-limited, leaving no functional or anatomic residuals. In the more severe and diffuse cases, temporary hyperthyroidism is common, and in those same cases temporary subclinical hypothyroidism often occurs.,5 4 The rare reported instances of permanent clinical hypothyroidism usually have causes other than subacute thyroiditis, such as a previous subtotal thyroidectomy or Hashimoto's thyroiditis.'4"'5 We have found many patients with temporary hyperthyroidism but none with permanent hypothyroidism. We have not carried out long-term follow-up studies on our patients, however. In this study we reviewed the first-visit characteristics of 269 patients with painful subacute thyroiditis. Of these patients, 90% were aged 20 to 59 years, with comparable age patterns for male and female patients. The mean age of our patients was 37.1 years; the mean age in most other reports has been at least 40.4-6,91 2 For the entire series, there was a preponderance of female to male patients (6.7:1), slightly higher than in most reports in the literature. The distribution
2019 _
8-
1614 13 -
12
c
.- 1
ci
a-
12.1 11.3
-1111
10.2
9.1 9/
/z9.4 X// ~~~~~7.9
91
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Month Figure 2.-The seasonal distribution of all 269 patients is shown. The incidence is slightly less in April through August and in December, but these variations are not statistically significant.
50
150 200 100 Days Since Diagnosis Figure 3.-The graph correlates the time from the beginning of pain to the disappearance of pain and palpable abnormalities in 70 patients observed through the course of the disease. In all instances, pain and tenderness ceased first. The mean duration of pain was 65 days versus 84 days for palpable 0
abnormalities.
THE WESTERN JOURNAL OF MEDICINE * JULY 1991
*
155 *
1
of whites, Japanese, and other races reflected that expected at the Straub Clinic. In about two thirds of the patients, the distribution was bilateral and in a third it was unilateral, either diffuse or localized. This anatomic distribution is similar to observations from other areas. 516.17 Our seasonal trends differ from some previous reports. Three studies found more cases diagnosed in summer than during other seasons. The peak months were July and August in Italy,4 June through August in Japan,3 and December through May in Australia.12 The concurrence of subacute thyroiditis and viral activity, particularly enteroviruses, was discussed by these investigators. By contrast, a study from Minnesota9 found no seasonal trends or relationship with enteroviruses. The study was population based rather than a review of clinical cases, as in the other reports. Similarly, a study from Finland6 found no seasonal differences. Our cases clearly did not cluster in the summer months. Our peak incidence period included January through March, three of the coolest months in Hawaii. The percentage of cases dropped beginning in April, when temperatures become warmer, and remained low through August, one ofthe hottest months. The available studies do not indicate a consistent seasonal pattern across different geographic regions. Because treatment is limited to pain relief and justifiable reassurance, it is important to provide a reasonable estimate of the duration of the signs and symptoms a patient will experience. The results of our study of 70 patients observed through the course ofthe disease answer some ofthe patient's concerns. The mean duration of pain was 2.2 months, and the mean duration of palpable abnormalities was 2.8 months. For a few patients lumps or irregularities persisted for many weeks after pain and tenderness were gone. Painful subacute thyroiditis in Hawaii appears to be similar to the disease in other areas. It is much more common in women, and most cases appeared in patients aged 20 through 60 years. The disease is likely to start in both lobes or to extend later to the opposite lobe rather than to remain unilateral. Noteworthy in our study was the delay between the disappearance of pain and tenderness and the regression of
63
palpable lumps. It is during this window, which may last many months, that diagnostic difficulty can arise. The firm or hard lumps are easily confused with cancer,"1 and unnecessary surgical therapy has been reported. '- 1518 For this reason, the diagnosis of subacute thyroiditis should be considered for patients presenting with firm or hard lumps or irregularities of the thyroid gland despite the absence of tenderness. A careful history of pain and tenderness will usually point to the correct diagnosis. If such a history is not obtained or clinical findings are suspicious for thyroid neoplasm, consideration should be given to obtaining a cytologic diagnosis with a fine-needle aspiration biopsy. REFERENCES 1. Volpe R: Subacute (de Quervain's) thyroiditis. Clin Endocrinol Metab 1979; 8:81-95 2. Nyulassy S, Hnilica P, Buc M, et al: Subacute (de Quervain's) thyroiditis: Association with HLA-Bw35 antigen and abnormalities of the complement system, immunoglobulins and other serum proteins. J Clin Endocrinol Metab 1977; 45: 270-274 3. Saito SS, Sakurada T, Yamamoto M, et al: Subacute thyroiditis: Observations on 98 cases for the last 14 years. Tohoku J Exp Med 1974; 113:141-147 4. Martino E, Buratti L, Bartalena L, et al: High prevalence of subacute thyroiditis during summer season in Italy. J Endocrinol Invest 1987; 10:321-323 5. Croxson M: Is that sore throat subacute thyroiditis? (Letter) NZ Med J 1986; 99:23 6. Oksa H, Jarvenpaa P, Metsahonkala L, Pasternack A, Leinikki P: No seasonal distribution in subacute de Quervain's thyroiditis in Finland (Letter). J Endocrinol Invest 1989; 12:495 7. Vanderline RJ, Milne J: Subacute thyroiditis-With special emphasis on the problem of early recognition. JAMA 1960; 16:1799-1802 8. Murray IPC, Steward RDH, Indyk JS: The diagnosis ofthe painful thyroid. Med J Australia 1970; 2:1055-1061 9. Furszyfer J, McConahey WM, Wahner HW, et al: Subacute (granulomatous) thyroiditis in Olmsted County, Minnesota. Mayo Clin Proc 1970; 45:396-404 10. Greene JN: Subacute thyroiditis. Am J Med 1971; 51:97-108 11. Hay ID: Thyroiditis: A clinical update. Mayo Clin Proc 1985; 60:836-843 12. Kitchener MI, Chapman IM: Subacute thyroiditis: A review of 105 cases. Clin Nucl Med 1989; 14:438-442 13. Nordyke RA, Gilbert Fl Jr, Harada ASM: Graves' disease: Influence of age on clinical findings. Arch Intern Med 1988; 148:626-631 14. Tikkanen MJ, Lamberg BA: Hypothyroidism following subacute thyroiditis. Acta Endocrinol 1982; 101:348-353 15. Gozariu L, Stroe M, Vladutiu T, Yepez-Escobar NG, et al: Late hypothyroidism following subacute thyroiditis. Exp Clin Endocrinol 1986; 87:48-52 16. Schultz A: Subacute diffuse thyroiditis: Clinical and laboratory findings in 24 patients and the effect of treatment with adrenal steroids. Postgrad Med 1961; 29:76-85 17. HamburgerJI: Thyroid disease, In Clinical Exercises in Intemal Medicine, Vol 1. Philadelphia, Pa, WB Saunders, 1978, pp 264-265 18. Volpe R, Johnston M: Subacute thyroiditis: A disease commonly mistaken for pharyngitis. Can Med Assoc J 1957; 77:297-307
Conferences & Reviews
Painful Subacute Thyroiditis in Hawaii ROBERT A. NORDYKE, MD; FRED I. GILBERT, Jr, MD; and CHRIS LEW, MD, Honolulu, Hawaii
Between 1960 and 1982 we prospectively studied 269 patients with painful subacute thyroiditis to determine the demographic characteristics, seasonality, and natural course of the disease. The mean age for all patients was 37.1 years. The female:male ratio was 6.7:1. At the first visit, disease was bilateral in 690/o. No epidemic or seasonal pattern was identified. The mean duration of thyroid tenderness was 2.2 months and that of palpable thyroid lumps was 2.8 months. This time difference, sometimes lasting many months, left a painfree "window" during which the palpable hard residual mass of subacute thyroiditis may be confused with other thyroid problems, especially cancer. (Nordyke RA, Gilbert Fl Jr, Lew C: Painful subacute thyroiditis in Hawaii. West J Med 1991 Jul; 155:61-63)
Subacute (de Quervain's) thyroiditis is an inflammatory condition of the thyroid probably caused by a virus, with a possible genetic predisposition."2 It can be localized or generalized, mild or severe, lasting weeks to many months. At different stages it may be confused with a "sore throat," the hyperthyroidism of Graves' disease, thyroid cancer, or bleeding into a cyst. Various authors report a female:male ratio of 3:1 to 7:1 and a peak incidence between 40 and 50 years of age.3`6 Based on the number of patients seen at major hospitals, the incidence of the disease has been hypothesized to be higher on the West Coast of the United States compared to the East,'-8 but this has been questioned.9 The incidence appears to be highly variable worldwide.8'0"' Some studies have reported a significant increase during the summer months,3.4"12 and others have found no seasonal trend.6'9 Excellent general reviews of subacute thyroiditis are available. 1"1l We examined the demographic characteristics (age, sex, and race) and the seasonal occurrence of disease of 269 patients with painful subacute thyroiditis seen at Straub Clinic in Hawaii. In addition, the clinical course of 70 patients was studied with special attention to the painfree "window" the time between the cessation of tenderness and the disappearance of palpable thyroid abnormalities attributable to thyroiditis. Patients seen for the first time during this window are likely to be misdiagnosed because tenderness is absent and the gland often feels unusually hard and irregular. Patients and Methods Study Population This study included all patients referred to the thyroid clinic of Straub Clinic in Honolulu between 1960 and 1982 who were diagnosed with painful subacute thyroiditis. Some patients were referred by outer-island physicians, but most were sent to us by Straub Clinic physicians (ranging from 36 in 1960 to 105 in 1982). During that time, Straub was entirely a fee-for-service facility, caring for about 15% of the civilian population of the island of Oahu. All patients had thyroid gland tenderness at their first visit or by recent history (we excluded patients falling into the
more recently described nontender variants""2). There were 269 such cases. Of these, 70 were observed through the course of their disease.
Patient Examination Clinical examination was similar in all patients, using a standardized work sheet II that contained the referral source, reason for the referral, demographic information (age, sex, and race), chief complaint, present illness, history of thyroid disease, physical findings related to the thyroid, clinical impression, and final diagnosis after all data became available. The diagnosis was made on the basis of typical signs and symptoms, including tenderness corresponding to a palpable mass, with pain often radiating to the ipsilateral jaw and ear, and clinical follow-up. When needed for confirmation, laboratory tests were obtained, including serum thyroxine estimates, iodine 131 thyroidal uptake at 6 or 24 hours, erythrocyte sedimentation rate, and thyroid scan. On the first visit, special attention was given to the time symptoms began, severity of symptoms, the initial location of pain and tenderness, thyroid gland size and palpation characteristics, and anatomic areas of tenderness and enlargement (localized, unilateral nonlocalized, or bilateral). On follow-up visits, special attention was given to gland size, palpable enlargements, tenderness, the correspondence of enlargements and tenderness, the migration of findings, and the time of the disappearance of tenderness and palpable abnormalities.
Results Demographic Characteristics Among the 269 patients, 47% were white, 24% Japanese, and the rest were various other races. The white:Japanese ratio was 2:1. This ratio is 1.8:1 for all of Straub Clinic's patients. The mean age was 37.1 years with a range from 4 to 86. Most cases (77%) occurred between ages 20 and 49 (Figure 1). The age distribution for male and female patients was similar. Female cases predominated at all ages, accounting for 87% of the 269 cases and giving a female:male ratio of 6.7:1. Among the 70 patients observed through the course of their illness, women predominated by a ratio of 6.1:1; 46%
From the Department of Nuclear Medicine, Straub Clinic & Hospital (Drs Nordyke and Gilbert), and the Department of Medicine, University of Hawaii John A. Burns School of Medicine (Drs Nordyke, Gilbert, and Lew), Honolulu, Hawaii. Grant support for this project was provided by the George F. Straub Trust and the Pacific Health Research Institute, Honolulu, Hawaii. Reprint requests to Robert A. Nordyke, MD, Straub Clinic & Hospital, 888 S King St, Honolulu, HI 96813.
SUBACUTE THYROIDITIS IN HAWAII
62 10-
3529.4
10-
-R2
22.3
12
a-i
15 -13.2
1 10
I
4.930
5-
1.1
7/
u ,_
/
A--~~~3.
0.8
j
10-19 20-29 30-39 40-49 50-59 60-69 70-79 80-89 Age, years Figure 1.-The graph depicts the age distribution by decade of 269 patients with painful subacute thyroiditis. 0-9
were white and 27% were Japanese. The mean age for female patients was 41.1 years with a range of 11 to 80.
Seasonal Variation The distribution of cases diagnosed in each month throughout the year is presented in Figure 2. There was no summer peak, in contrast to the findings of some reports.3'4" 2 The only apparent trend, a lower percentage of cases in April through August compared with September through March, was not statistically significant. The one exception to this trend was the low incidence in December.
Localization Within the Thyroid Gland When cases were categorized by area of the gland involved on the first visit, the area was discretely localized in 16%, nonlocalized but unilateral in 15%, and bilateral-usually diffuse, and including those that had migrated by the time of the first observation-in 69%. All three categories of involvement were more common in white patients than in Japanese. Duration of Tenderness and Palpable Lumps The progress of tenderness and palpable lumps was observed for 70 patients throughout the course of their disease. The time symptoms began was estimated by history obtained at the first visit. Tenderness and palpable lumps disappeared
at about the same time in 50 patients (72%), and in the other 20 patients (28%) tenderness ceased first, leaving areas of firm or hard lumps that disappeared later. The duration of tenderness for the entire group was 65.4 + 42.5 days (mean + standard deviation). The duration of palpable abnormalities that later disappeared spontaneously was 83.5 ± 51.5 days. Two patients had prolonged, severe, debilitating pain and tenderness poorly responsive to treatment with prednisone. One had a near-total thyroidectomy and the other an ablative dose of sodium iodide 1 131. Both became free of pain and tenderness after their definitive treatment. The percentages of patients with pain and palpable abnormalities at various times after the disease occurred are given in Figure 3, which illustrates the magnitude of the painfree window. More patients continued to have palpable abnormalities than persistent pain at any given duration of follow-up. The figure also shows the broad range of durations of pain and palpable lumps. Some patients were symptomfree within a week or two; for others, pain and palpable irregularities persisted for months.
Discussion The diagnosis of painful subacute thyroiditis can usually be made on clinical grounds alone. In nearly all instances, its course is benign and self-limited, leaving no functional or anatomic residuals. In the more severe and diffuse cases, temporary hyperthyroidism is common, and in those same cases temporary subclinical hypothyroidism often occurs.,5 4 The rare reported instances of permanent clinical hypothyroidism usually have causes other than subacute thyroiditis, such as a previous subtotal thyroidectomy or Hashimoto's thyroiditis.'4"'5 We have found many patients with temporary hyperthyroidism but none with permanent hypothyroidism. We have not carried out long-term follow-up studies on our patients, however. In this study we reviewed the first-visit characteristics of 269 patients with painful subacute thyroiditis. Of these patients, 90% were aged 20 to 59 years, with comparable age patterns for male and female patients. The mean age of our patients was 37.1 years; the mean age in most other reports has been at least 40.4-6,91 2 For the entire series, there was a preponderance of female to male patients (6.7:1), slightly higher than in most reports in the literature. The distribution
2019 _
8-
1614 13 -
12
c
.- 1
ci
a-
12.1 11.3
-1111
10.2
9.1 9/
/z9.4 X// ~~~~~7.9
91
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Month Figure 2.-The seasonal distribution of all 269 patients is shown. The incidence is slightly less in April through August and in December, but these variations are not statistically significant.
50
150 200 100 Days Since Diagnosis Figure 3.-The graph correlates the time from the beginning of pain to the disappearance of pain and palpable abnormalities in 70 patients observed through the course of the disease. In all instances, pain and tenderness ceased first. The mean duration of pain was 65 days versus 84 days for palpable 0
abnormalities.
THE WESTERN JOURNAL OF MEDICINE * JULY 1991
*
155 *
1
of whites, Japanese, and other races reflected that expected at the Straub Clinic. In about two thirds of the patients, the distribution was bilateral and in a third it was unilateral, either diffuse or localized. This anatomic distribution is similar to observations from other areas. 516.17 Our seasonal trends differ from some previous reports. Three studies found more cases diagnosed in summer than during other seasons. The peak months were July and August in Italy,4 June through August in Japan,3 and December through May in Australia.12 The concurrence of subacute thyroiditis and viral activity, particularly enteroviruses, was discussed by these investigators. By contrast, a study from Minnesota9 found no seasonal trends or relationship with enteroviruses. The study was population based rather than a review of clinical cases, as in the other reports. Similarly, a study from Finland6 found no seasonal differences. Our cases clearly did not cluster in the summer months. Our peak incidence period included January through March, three of the coolest months in Hawaii. The percentage of cases dropped beginning in April, when temperatures become warmer, and remained low through August, one ofthe hottest months. The available studies do not indicate a consistent seasonal pattern across different geographic regions. Because treatment is limited to pain relief and justifiable reassurance, it is important to provide a reasonable estimate of the duration of the signs and symptoms a patient will experience. The results of our study of 70 patients observed through the course ofthe disease answer some ofthe patient's concerns. The mean duration of pain was 2.2 months, and the mean duration of palpable abnormalities was 2.8 months. For a few patients lumps or irregularities persisted for many weeks after pain and tenderness were gone. Painful subacute thyroiditis in Hawaii appears to be similar to the disease in other areas. It is much more common in women, and most cases appeared in patients aged 20 through 60 years. The disease is likely to start in both lobes or to extend later to the opposite lobe rather than to remain unilateral. Noteworthy in our study was the delay between the disappearance of pain and tenderness and the regression of
63
palpable lumps. It is during this window, which may last many months, that diagnostic difficulty can arise. The firm or hard lumps are easily confused with cancer,"1 and unnecessary surgical therapy has been reported. '- 1518 For this reason, the diagnosis of subacute thyroiditis should be considered for patients presenting with firm or hard lumps or irregularities of the thyroid gland despite the absence of tenderness. A careful history of pain and tenderness will usually point to the correct diagnosis. If such a history is not obtained or clinical findings are suspicious for thyroid neoplasm, consideration should be given to obtaining a cytologic diagnosis with a fine-needle aspiration biopsy. REFERENCES 1. Volpe R: Subacute (de Quervain's) thyroiditis. Clin Endocrinol Metab 1979; 8:81-95 2. Nyulassy S, Hnilica P, Buc M, et al: Subacute (de Quervain's) thyroiditis: Association with HLA-Bw35 antigen and abnormalities of the complement system, immunoglobulins and other serum proteins. J Clin Endocrinol Metab 1977; 45: 270-274 3. Saito SS, Sakurada T, Yamamoto M, et al: Subacute thyroiditis: Observations on 98 cases for the last 14 years. Tohoku J Exp Med 1974; 113:141-147 4. Martino E, Buratti L, Bartalena L, et al: High prevalence of subacute thyroiditis during summer season in Italy. J Endocrinol Invest 1987; 10:321-323 5. Croxson M: Is that sore throat subacute thyroiditis? (Letter) NZ Med J 1986; 99:23 6. Oksa H, Jarvenpaa P, Metsahonkala L, Pasternack A, Leinikki P: No seasonal distribution in subacute de Quervain's thyroiditis in Finland (Letter). J Endocrinol Invest 1989; 12:495 7. Vanderline RJ, Milne J: Subacute thyroiditis-With special emphasis on the problem of early recognition. JAMA 1960; 16:1799-1802 8. Murray IPC, Steward RDH, Indyk JS: The diagnosis ofthe painful thyroid. Med J Australia 1970; 2:1055-1061 9. Furszyfer J, McConahey WM, Wahner HW, et al: Subacute (granulomatous) thyroiditis in Olmsted County, Minnesota. Mayo Clin Proc 1970; 45:396-404 10. Greene JN: Subacute thyroiditis. Am J Med 1971; 51:97-108 11. Hay ID: Thyroiditis: A clinical update. Mayo Clin Proc 1985; 60:836-843 12. Kitchener MI, Chapman IM: Subacute thyroiditis: A review of 105 cases. Clin Nucl Med 1989; 14:438-442 13. Nordyke RA, Gilbert Fl Jr, Harada ASM: Graves' disease: Influence of age on clinical findings. Arch Intern Med 1988; 148:626-631 14. Tikkanen MJ, Lamberg BA: Hypothyroidism following subacute thyroiditis. Acta Endocrinol 1982; 101:348-353 15. Gozariu L, Stroe M, Vladutiu T, Yepez-Escobar NG, et al: Late hypothyroidism following subacute thyroiditis. Exp Clin Endocrinol 1986; 87:48-52 16. Schultz A: Subacute diffuse thyroiditis: Clinical and laboratory findings in 24 patients and the effect of treatment with adrenal steroids. Postgrad Med 1961; 29:76-85 17. HamburgerJI: Thyroid disease, In Clinical Exercises in Intemal Medicine, Vol 1. Philadelphia, Pa, WB Saunders, 1978, pp 264-265 18. Volpe R, Johnston M: Subacute thyroiditis: A disease commonly mistaken for pharyngitis. Can Med Assoc J 1957; 77:297-307
