HISTORY

An 84-year-old woman seen for annual complete history and physical examination in nursing home where she has lived for the past year. Biopsy-proven sarcoidosis several decades ago caused a central scalp area of alopecia, but it is not clear whether there were ever pulmonary features. Present respiratory problems limited to bronchospasm that flares easily and often but is controlled with courses of corticosteroids and nebulizer treatments.

Has dryness of eyes of unknown date of onset, but no dry mouth. No recent trauma to eyes.

Lucid, articulate woman who bears her frailty with stoicism and maintains friendly interaction with the staff. Vital signs normal. Skin without nodules. Face as illustrated. Bumps near the eyes are soft and nontender.

Free of focal neurologic deficit, although globally weak. Mental status examination reveals good cognitive function; however, she has a dependent personality, is emotionally labile, and displays easy weepiness.

This case is a first for "What's Your Diagnosis?": it focuses on a mistake in diagnostic reasoning. When the senior author of this column first met the patient, he thought that her dry eye was the result of sarcoidal inflammation of the lacrimal glands, which can produce a keratoconjunctivitis sicca syndrome. "Evidence" of sarcoidal dacryoadenitis was inferred from the prominent pads or bags seen in the medial portion of both upper eyelids, but especially the right (Figure 1).

When these areas were touched, however, they felt like little sacs of water under the skin. The texture excluded infiltrated lacrimal gland, which should be rubbery to quite firm. It also made a neoplasm most unlikely--as did the lack of abnormal epithelium overlying the lesions. Xanthelasma also ought not to be this soft. Thus, the yellow cast had to be explained by another mechanism than cholesterol in macrophages. Neutral fat supplied the explanation.

So the differential diagnosis became, generically, localized edema versus fat pads. The examiner could not produce pitting in these areas, nor in the larger and more diffuse sacs beneath the eyes, by applying pressure. Hence, edema was considered highly unlikely: even if this were "nonpitting" edema, it should have been indurated as a result of fibrosis. Such scarring in the skin and subcutis is what causes long-standing edema to lose the ability to bear a temporary dent.

If localized edema from hymenoptera envenomation (bee sting or wasp sting) were proposed, one would have to account for bilaterality and a negative history in a competent historian. If these inconsistencies could be surmounted, one would still be left trying to explain the softness, because the fluid transudation after a sting typically makes the swollen region firmer than the surrounding tissue.

Localized fat accumulation in the form of fat pads was diagnosed. Age and previous high-dose systemic corticosteroid therapy predisposed the patient to lipoma-like accretions of adipocytes. Because neutral fat is liquid at room temperature, it felt, through the very thin skin of the lids, exactly as soft as melted butter. There is no traumatic mechanism whereby fat can wind up in these locales, including trauma from external injury or blunt injury (such as in a motor vehicle accident), nor from any sort of cosmetic procedure, including the therapeutic injection of botulinum toxin. Over and above the negative history, botulinum toxin injection becomes much less likely because of the intact forehead wrinkling that is seen clearly in the index image at the start of this article.

Thorough grounding in anatomy remains essential to physical diagnosis and has been made easier by the frequent demonstrations we all see on CT and MRI imaging. Even before palpation, an intern reviewing the case dismissed the hypothesis of lacrimal infiltration because the major lacrimal glands are situated laterally, not medially. However, there are minor accessory lacrimal glands in the medial part of the upper orbit; sarcoid infiltration of these glands has been reported. Nevertheless, to see such a phenomenon without a corresponding infiltration laterally would be most unusual. So one's grounding in basic science proved chastening and, what is more to the point, instructive. Neither of the 2 authors of this column will ever mistake a fat pad in this site for anything else! The senior author ultimately reached a correct conclusion by cross-checking inspection with a second modality--palpation; that kept him open to the possibility of error. A defective diagnostic hypothesis was discarded.

The patient recounted having had a biopsy of some tissue in the 1960s that was said to have secured the diagnosis of sarcoidosis. Neither the report nor the slides could be located despite repeated efforts. We did not believe she was confabulating or displaying Münchhausen syndrome. Instead, two bedside features corroborated her story.

First, she had initially had dyspnea without wheezing, and this symptom cleared after high-dose corticosteroid therapy. The lack of any recurrent symptoms in the decades that followed strongly suggested that this was not simply a first attack of the asthma that developed in old age and then plagued her with no long symptom-free periods. Second, localized alopecia developed soon after the sarcoid was diagnosed, and the patient was told by a dermatologist that hair would never again grow in the area. The coexistence of this scarring alopecia (Figure 2), as distinct from a nonscarring separate process such as alopecia areata, supported the diagnosis of sarcoidosis.

Many skin and eye findings can occur in sarcoidosis. Some have been reviewed in a previous column on this condition.¹ Figure 3 illustrates dramatic dermopathy in another patient. Other findings are detailed in textbooks^2,3 and reviews.

Ocular findings occur in some 30% of patients with sarcoidosis. Uveitis is the most familiar ocular manifestation. Granulomas of the lids in sarcoid can be mistaken for chalazion, a far more common problem. Sarcoid granulomas can be found in the conjunctiva, lacrimal gland, and even the choroid. All of these can sometimes be diagnosed at the bedside by the non-ophthalmologist even before the consultant has been called in. Iris nodules, vitreitis, and perivenular retinal inflammation may require the specialist's equipment, such as the slit lamp or fluorescein(Drug information on fluorescein) angiography, as well as the ophthalmologist's specialized knowledge base. Biopsy of conjunctiva or lacrimal gland can yield a histopathologic diagnosis.⁴ Nevertheless, the knowledge, attention, and observational skills of the clinician remain the foremost tools of diagnosis.

In this regard, it is hoped that some readers are champing at the bit, saying, "What about the Queen Anne sign?" This sign led us to "recheck" the patient's thyroid function, which revealed mild hypothyroidism, for which thyroxine was then prescribed. We discovered that routine measurement of thyroid-stimulating hormone on admission to the nursing home had inadvertently been omitted, until the bedside led to the laboratory, rather than, as seems the almost inevitable sequence nowadays, the other way around!

Armed with a heightened awareness of medial periorbital fat pads, we began to see them in other aged persons, some of whom had not had the corticosteroid exposure we had postulated as a causative element in our patient (Figures 4 and 5). The dramatic finding often makes it easier to pick up the subtler variant, but the case illustrated was overpowering in its prominence.

Now, about once every 2 years, an interested trainee will come to ask one of us to look at "nodules" just below a patient's eyebrows that turn out to be the same finding.

Schneiderman H, Jalal R. Medial periorbital fat pads mimicking lacrimal infiltration by sarcoidosis, and the process of diagnostic reasoning. CONSULTANT. 2005;45:479-482.