Photoinduced dermal pigmentation in patients taking tricyclic antidepressants: histology, electron microscopy, and energy dispersive spectroscopy

Drug-Induced Pigmentation: A Review

Drug-induced pigmentation (DIP) is estimated to account for 20% of all cases of acquired hyperpigmentation. Over 50 agents have been implicated, including antibiotics, antimalarials, antiretrovirals, antipsychotics, prostaglandin analogs, heavy metals, and chemotherapeutic agents. The skin, mucosal surfaces, nails, and hair can all be affected, with the color, distribution, onset, and duration of pigmentation varying between offending agents. Both a thorough physical examination and medication history are necessary to determine the offending agent. In terms of mechanism, DIP occurs most frequently through the accumulation of melanin within the dermis but also by drug accumulation, pigment synthesis, and iron deposition. Photoprotection, including applying a broad-spectrum sunscreen, wearing photoprotective clothing, and seeking shade, plays an important role in the prevention of exacerbation of DIP. Multiple lasers, including the picosecond alexandrite, Q-switched Nd:YAG, Q-switched alexandrite, and Q-switched ruby lasers, have been successful in obtaining clearance of DIP. In this review, we examine the unique characteristics of each of the inciting agents in terms of incidence, clinical presentation, time to onset and resolution, and pathogenesis.

Tricyclic antidepressant-induced photosensitivity; A case report and systematic review

BACKGROUND/PURPOSE

Tricyclic antidepressants (TCAs) are still widely used and are available to purchase without prescription in some countries. Awareness of adverse cutaneous drug reactions is essential.

METHOD

We reported a case of photo-distributed hyperpigmentation due to imipramine and carried out a systematic search of the related articles using the search terms "tricyclic antidepressants" or "tricyclic antidepressive agents", and "hyperpigmentation" or "photosensitivity disorder". Fifty non-duplicate citations were identified of which 28 articles which were independently assessed in full. The review was registered in PROSPERO, CRD42018107338.

RESULTS

The remaining 25 articles met our inclusion criteria. Photo-distributed hyperpigmentation tricyclic antidepressant-induced photosensitivity reactions (TIPs) was the most common presentation. In 21 cases, this presented as an asymptomatic discolouration of exposed sites. Imipramine (81%), amitriptyline (9.5%), desipramine hydrochloride (4.8%) and mirtazapine (4.8%) were reported to be the culprit drugs. Nineteen were female with a mean age at presentation of 55 years. Mean duration from commencing the culprit drug until the development of discolouration was 10.4 years. Mean daily dose was 222.7 mg for imipramine. Histology was characteristic with golden-brown or brownish granules deposited in dermis. Staining for Masson-Fontana and MEL-5 was positive in all cases. Phototesting had not been done in cases prior to ours (negative 3 months after discontinuation of imipramine). Three further reports of suspected TIP presented with non-specific and eczematous eruption. The two presentations were reported along with systemic problems (thrombocytopenia and hepatic injury).

CONCLUSIONS

This systematic review highlights the characteristic features of exposed site hyperpigmentation of TCA-induced photosensitivity occurring after prolonged drug exposure in many cases.

Drug-Induced Photosensitivity-An Update: Culprit Drugs, Prevention and Management

Photosensitive drug eruptions are cutaneous adverse events due to exposure to a medication and either ultraviolet or visible radiation. In this review, the diagnosis, prevention and management of drug-induced photosensitivity is discussed. Diagnosis is based largely on the history of drug intake and the appearance of the eruption primarily affecting sun-exposed areas of the skin. This diagnosis can also be aided by tools such as phototesting, photopatch testing and rechallenge testing. The mainstay of management is prevention, including informing patients of the possibility of increased photosensitivity as well as the use of appropriate sun protective measures. Once a photosensitivity reaction has occurred, it may be necessary to discontinue the culprit medication and treat the reaction with corticosteroids. For certain medications, long-term surveillance may be indicated because of a higher risk of developing melanoma or squamous cell carcinoma at sites of earlier photosensitivity reactions. A large number of medications have been implicated as causes of photosensitivity, many with convincing clinical and scientific supporting evidence. We review the medical literature regarding the evidence for the culpability of each drug, including the results of phototesting, photopatch testing and rechallenge testing. Amiodarone, chlorpromazine, doxycycline, hydrochlorothiazide, nalidixic acid, naproxen, piroxicam, tetracycline, thioridazine, vemurafenib and voriconazole are among the most consistently implicated and warrant the most precaution by both the physician and patient.

An Update on Drug-Induced Pigmentation

Drug-induced pigmentation accounts for up to 20% of all cases of acquired pigmentation. A thorough review of medical history and previous and ongoing medications as well as a complete skin examination can guide diagnosis. Implicated agents include alkylating/cytotoxic agents, analgesics, antiarrhythmics, anticoagulants, antiepileptics, antimalarials, antimicrobials, antiretrovirals, metals, prostaglandin analogs, and psychotropic agents, among others. Confirming true drug associations can be challenging, especially in the setting of delayed onset of pigmentation and coexisting polypharmacy.

Combination effects of airborne particulate matter exposure and high-fat diet on hepatic fibrosis through regulating the ROS-endoplasmic reticulum stress-TGFβ/SMADs axis in mice

BACKGROUND

Hepatic fibrosis, characterized by an excessive accumulation of extracellular matrix, is associated with toxic substance exposure, chronic infections, mechanical injury, airborne fine particulate matter (PM_2.5) exposure and metabolic disease. This study aimed to investigate the effect and mechanism of long-term, real-world airborne particulate matter (PM) exposure on hepatic fibrosis and further explored whether combination treatment of PM exposure and high-fat diet (HFD) aggravate the adverse effects in mice.

METHODS AND RESULTS

Six-week-old male C57BL/6J mice fed with either a standard chow diet (STD) or an HFD were treated with either filtered air (FA) or PM for 18 weeks. Metabolic parameters, histological examination, gene expression analysis, and Western blot analysis were utilized to measure the effect and mechanism of PM exposure on hepatic fibrosis and to further analyze the synergistic effect of HFD. Subchronic airborne PM exposure induces hepatic fibrosis in mice, and combination treatment of PM exposure and HFD accelerate the adverse effect. Meanwhile, subchronic exposure to real-world PM increased the level of hepatic ROS, and the expression of endoplasmic reticulum (ER) stress markers (GRP78 and CHOP), p-SMAD2 and p-SMAD3, as well as up-regulated TGFβ and collagen 1 in liver tissues. Furthermore, PM exposure and HFD displayed the synergistic effects on these changes in liver.

CONCLUSION

Our findings indicate that airborne PM exposure aggravates HFD -induced hepatic fibrosis. The ROS-ER stress-TGFβ/SMADs regulatory axis mediates the effects of airborne PM exposure on accelerating hepatic fibrosis.

Pigmented Deposits in the Skin

Pigmented deposits can occur in the skin due to many and varied causes. Some of them are systemic conditions accompanied by involvement of internal organs. Others have serious prognostic implications, and early diagnosis can help in the correct and adequate management of the diseases. In addition, some of them are quite innocuous and the correct diagnosis avoids unnecessary treatments. In this article, we review the morphologic features of some of the most common and some of the less usual pigmented deposits in skin other than tattoos.

Imipramine-Induced Facial Pigmentation: Case Report and Literature Review

Background:

Patients who present with facial pigmentation can be a diagnostic challenge. ObjectiveThe goal of this study was to discuss the diagnosis and management of imipramine-induced facial pigmentation.

Methods:

We describe a patient with facial pigmentation of 26 years' duration that was associated with imipramine treatment for depression. We discuss light and election microscopic findings and review 11 previously reported cases of imipramine-induced skin pigmentation.

Results:

Examination showed blue-gray facial pigmentation. Light microscopy showed perivascular pigment granule deposits in the upper dermis that stained positively with Fontana–Masson stain and negatively with Prussian blue stain. Electron microscopy showed electron-dense bodies within histiocytes without clearly identifiable melanin granules, consistent with drug-induced pigmentation. Six weeks after switching to sertraline the patient reported a slight improvement of her cutaneous pigmentation.

Conclusion:

Imipramine is a rare cause of gray-blue facial pigmentation. Light microscopy consistently shows granular dermal deposits that stain positively with Fontana-Masson stain but negatively with iron stain.

Drug-induced photosensitivity: culprit drugs, management and prevention

Photo-induced drug eruptions are cutaneous adverse events due to exposure to a drug and either ultraviolet or visible radiation. Based on their pathogenesis, they can be classified as phototoxic or photoallergic drug eruptions, although in many cases it is not possible to determine whether a particular eruption is due to a phototoxic or photoallergic mechanism. In this review, the diagnosis, prevention and management of drug-induced photosensitivity are discussed. Diagnosis is based primarily on the history of drug intake and the clinical appearance of the eruption, primarily affecting sun-exposed areas of the skin. Phototesting and photopatch testing can be useful adjuncts in making a diagnosis. The mainstay of management is prevention, including informing patients of the possibility of increased sun sensitivity and the use of sun protective measures. However, once the eruption has occurred, it may be necessary to discontinue the culprit medication and treat the eruption with a potent topical corticosteroid. Drugs that have been implicated in causing photosensitive eruptions are reviewed. Tetracycline, doxycycline, nalidixic acid, voriconazole, amiodarone, hydrochlorothiazide, naproxen, piroxicam, chlorpromazine and thioridazine are among the most commonly implicated medications. We review the medical literature regarding evidence for the culpability of each drug, including the results of phototesting, photopatch testing and rechallenge testing.

Airborne particulate matter selectively activates endoplasmic reticulum stress response in the lung and liver tissues

Recent studies have suggested a link between inhaled particulate matter (PM) exposure and increased mortality and morbidity associated with pulmonary and cardiovascular diseases. However, a precise understanding of the biological mechanism underlying PM-associated toxicity and pathogenesis remains elusive. Here, we investigated the impact of PM exposure in intracellular stress signaling pathways with animal models and cultured cells. Inhalation exposure of the mice to environmentally relevant fine particulate matter (aerodynamic diameter < 2.5 μm, PM(2.5)) induces endoplasmic reticulum (ER) stress and activation of unfolded protein response (UPR) in the lung and liver tissues as well as in the mouse macrophage cell line RAW264.7. Ambient PM(2.5) exposure activates double-strand RNA-activated protein kinase-like ER kinase (PERK), leading to phosphorylation of translation initiation factor eIF2α and induction of C/EBP homologous transcription factor CHOP/GADD153. Activation of PERK-mediated UPR pathway relies on the production of reactive oxygen species (ROS) and is critical for PM(2.5)-induced apoptosis. Furthermore, PM(2.5) exposure can activate ER stress sensor IRE1α, but it decreases the activity of IRE1α in splicing the mRNA encoding the UPR trans-activator X-box binding protein 1 (XBP1). Together, our study suggests that PM(2.5) exposure differentially activates the UPR branches, leading to ER stress-induced apoptosis through the PERK-eIF2α-CHOP UPR branch. This work provides novel insights into the cellular and molecular basis by which ambient PM(2.5) exposure elicits its cytotoxic effects that may be related to air pollution-associated pathogenesis.

Kupffer cell activation by ambient air particulate matter exposure may exacerbate non-alcoholic fatty liver disease

Owing to increased obesity, non-alcoholic fatty liver disease (NAFLD) is now the most prevalent liver disease in the United States. NAFLD is considered a component of metabolic syndrome, a cluster of disorders that also includes diabetes mellitus, dyslipidemia, arteriosclerosis, and hypertension. Exposure to ambient air particulate matter with aerodynamic diameters < 2.5 microm (PM(2.5)) is a risk factor for arteriosclerosis and lung disease, but its effect on NAFLD is unknown. PM(2.5) induces pulmonary dysfunction via Toll-like receptor (TLR) activation on alveolar macrophages. TLR activation of Kupffer cells, resident hepatic macrophages, and subsequent pro-inflammatory cytokine production have been shown to play a key role in NAFLD progression. We hypothesized that PM(2.5) exposure is a significant risk factor for the progression of NAFLD. Thus, following exposure of male C57BL/6 mice fed high fat chow (HFC) to concentrated air particulate matter (CAPs) or filtered air for 6 weeks, progression of NAFLD was evaluated by standardized histological assessment of hepatic inflammation and fibrosis. In mice fed HFC, the hepatic inflammatory grade (3.00 +/- 0.00 vs. 1.50 +/- 0.71, P < 0.001) and fibrosis stage (1.00 +/- 0.00 vs. 0.60 +/- 0.52, P = 0.023) were both significantly higher in mice exposed to CAPs versus filtered air, respectively. Increased numbers of Kupffer cells contained PM in CAPs-exposed mice scores of (2.00 +/- 0.94 vs. 0.20 +/- 0.42, respectively, P < 0.001). PM exposure increased IL-6 secretion up to seven-fold in a dose-dependent manner by isolated wild-type but not TLR4(-/-) Kupffer cells (P < 0.050). In conclusion, ambient PM(2.5) exposure may be a significant risk factor for NAFLD progression.

Kupffer cell activation by ambient air particulate matter exposure may exacerbate non-alcoholic fatty liver disease

Owing to increased obesity, non-alcoholic fatty liver disease (NAFLD) is now the most prevalent liver disease in the United States. NAFLD is considered a component of metabolic syndrome, a cluster of disorders that also includes diabetes mellitus, dyslipidemia, arteriosclerosis, and hypertension. Exposure to ambient air particulate matter with aerodynamic diameters < 2.5 microm (PM(2.5)) is a risk factor for arteriosclerosis and lung disease, but its effect on NAFLD is unknown. PM(2.5) induces pulmonary dysfunction via Toll-like receptor (TLR) activation on alveolar macrophages. TLR activation of Kupffer cells, resident hepatic macrophages, and subsequent pro-inflammatory cytokine production have been shown to play a key role in NAFLD progression. We hypothesized that PM(2.5) exposure is a significant risk factor for the progression of NAFLD. Thus, following exposure of male C57BL/6 mice fed high fat chow (HFC) to concentrated air particulate matter (CAPs) or filtered air for 6 weeks, progression of NAFLD was evaluated by standardized histological assessment of hepatic inflammation and fibrosis. In mice fed HFC, the hepatic inflammatory grade (3.00 +/- 0.00 vs. 1.50 +/- 0.71, P < 0.001) and fibrosis stage (1.00 +/- 0.00 vs. 0.60 +/- 0.52, P = 0.023) were both significantly higher in mice exposed to CAPs versus filtered air, respectively. Increased numbers of Kupffer cells contained PM in CAPs-exposed mice scores of (2.00 +/- 0.94 vs. 0.20 +/- 0.42, respectively, P < 0.001). PM exposure increased IL-6 secretion up to seven-fold in a dose-dependent manner by isolated wild-type but not TLR4(-/-) Kupffer cells (P < 0.050). In conclusion, ambient PM(2.5) exposure may be a significant risk factor for NAFLD progression.

Imipramine-induced hyperpigmentation: a case report and review of the literature

Imipramine-induced hyperpigmentation is rare with only 13 cases reported in the literature to date. We report a 64-year-old female who presented with blue-gray discoloration on her face present for 4-5 years. The patient's medications included imipramine for depression for approximately 23 years. Physical examination revealed slate-gray hyperpigmented discrete and coalescing macules of the malar cheeks and the bilateral temples and periorbitally. She also had diffuse gray pigmentation of the bilateral dorsal hands. Histologic examination revealed an unremarkable epidermis with golden-brown round globules clustered in the superficial dermis, which stained strongly positive with a Fontana-Masson stain. Prussian blue stain for hemosiderin was negative. A diagnosis of imipramine-induced hyperpigmentation was made. Imipramine-induced hyperpigmentation as well as a detailed review of drug-induced hyperpigmentation is discussed.

Chemical genetic screening identifies tricyclic compounds that decrease cellular melanin content

A screen of a library of 2,000 drugs and natural products in murine melanocytes identified 10 tricyclic antidepressants (TCAs) as compounds that potently decreased intracellular melanin content. The rank order of potency of these compounds for decreasing melanin content was different than their relative potencies as antidepressants. These compounds had no effect on either the level or the enzymatic activity of cellular tyrosinase (Tyr). Increased presence of both Tyr and melanin in the culture media was observed in treated melanocytes. Immunofluorescence localization revealed that these compounds decreased intracellular melanin content by disrupting the intracellular trafficking of Tyr gene family proteins. In treated melanocytes, Tyr, Tyr-related protein 1, and dopachrome tautomerase accumulated in enlarged granules distributed throughout the cytoplasm. Colocalization of Tyr with lysosome-associated membrane protein 1 was observed within many of these granules. Partial colocalization of Tyr with the Hermansky-Pudlak syndrome 1 gene product observed in control melanocytes was abolished by TCA treatment. Our results show that these compounds decreased intracellular melanin content by altering the trafficking of Tyr gene family proteins and inducing abnormal secretion of Tyr. Results from our screening have implications for the design of products for skin lightening and treatment of hyperpigmentation.

Imipramine-associated hyperpigmentation

OBJECTIVE

To inform clinicians of the potential for severe and persistent facial hyperpigmentation with the long-term use of imipramine.

CASE SUMMARY

A 65-year-old white male veteran with a history of paranoid schizophrenia was referred to the psychiatry service by a dentist who thought that the patient was both cyanotic and psychotic. The history and biopsy results indicated the possibility of imipramine-associated hyperpigmentation, only the second reported case in a male patient. The presentation was complex, with a history of neuroleptic exposure and multiple signs of parkinsonism. A brain single photon-emission computed tomography scan demonstrated frontal lobe hypermetabolism and bilateral caudate hypermetabolism, which normalized 14 months later. Despite discontinuation of imipramine, the patient continued to appear cyanotic, leading to worsening social isolation. He became known as "the man with the purple face." On his rare ventures outside the home, he was embarrassed by sporadic calls to 911 by persons fearing he was ill.

DISCUSSION

Although facial hyperpigmentation secondary to the use of phenothiazines has been reported frequently, it is much less common with imipramine, and is very rare in males. Failure to recognize this adverse reaction led to continuing treatment with imipramine and to an apparently irreversible condition. The brain imaging findings have no link with the hyperpigmenting process, but raise questions about neuroleptic-induced metabolic changes in the brain.

CONCLUSIONS

Clinicians need to be aware of rare adverse reactions such as hyperpigmentation, and be prepared to take appropriate and early action to prevent such reactions from becoming irreversible.

Photodistributed blue-gray pigmentation of the skin associated with long-term imipramine use

A 72-year-old white woman presented with progressively increasing slate-gray pigmentation of the face and extensor aspect of the forearms, which she had been suffering from for 8 years. She had been taking imipramine for approximately 30 years. Her other medications included ranitidine and anacin. Physical examination revealed slate-gray hyperpigmentation of the skin photodistributed on the face (Figs 1, 2) and extensor aspects of the forearms. Relative sparing of the skin folds, mucous membranes, sclerae, teeth, and nails was noted. The remainder of the physical examination revealed no abnormalities. Skin biopsy specimens from the right cheek and right forearm were obtained. Histologic examination revealed collections of variably sized, round to ovoid, yellow-brown globular deposits in the upper and mid dermis (Fig. 2). The deposits were identified within macrophages and free within the dermis. The epidermis was unremarkable and free of deposits. The deposits stained for melanin with a Fontana-Masson stain, but did not stain for iron.

Drug-induced skin pigmentation. Epidemiology, diagnosis and treatment

Drug-induced pigmentation represents 10 to 20% of all cases of acquired hyperpigmentation and this hypothesis must be systematically raised in unexplained pigmented lesions especially in elderly people. The pathogenesis of drug-induced pigmentation is variable according to the causative medication and can involve an accumulation of melanin, sometimes following a nonspecific cutaneous inflammation and often worsened by sun exposure, an accumulation of the triggering drug itself, a synthesis of special pigments under the direct influence of the drug or deposits of iron following damage to the dermal vessels. The influence of sun exposure is usually obvious in most cases, either by sun-induced melanin synthesis stimulation with formation of complexes between melanin and the causative drug or by transformation of the drug in visible particles usually taken up by dermal macrophages under the influence of sunlight. The main drugs implicated in causing skin pigmentation are nonsteroidal anti-inflammatory drugs, antimalarials, amiodarone, cytotoxic drugs, tetracyclines, heavy metals and psychotropic drugs. Clinical features are very variable according to the triggering molecule, with a large range of patterns and shades which are sometimes more or less reminiscent of the culprit drug. Histological findings are very variable as well but the colored particles are often concentrated within dermal macrophages which are sometimes localized in a distinctive fashion with respect to dermal structures such as vessels or adnexes. Treatment is often limited to sun-avoidance or interruption of treatment with the offending drug but laser therapy recently gave rise to hope of a cure in some cases. These measures are often followed by a fading of the lesions but the pigmentation may last for a long time or may even become permanent in a small percentage of patients.

Laser treatment of imipramine-induced hyperpigmentation

BACKGROUND

Blue or slate-gray hyperpigmentation is seen with a variety of medications, including imipramine. We describe a patient with significant imipramine-induced pigmentation.

OBJECTIVE

The purpose of this study was to describe an effective laser treatment resulting in improvement of imipramine-induced hyperpigmentation, without discontinuing the medication.

METHODS

The patient underwent treatment with carbon dioxide, erbium, alexandrite, and ruby lasers to hyperpigmented areas. Tissue biopsy specimens taken before treatment, immediately after treatment with the alexandrite laser, and at clearing were analyzed by light microscopy.

RESULTS

The Q-switched alexandrite and ruby lasers resulted in clinical improvement in the patient's hyperpigmentation and a decrease in pigment granules on light microscopy.

CONCLUSION

Both the Q-switched alexandrite and ruby lasers are effective treatments for imipramine-induced hyperpigmentation. The improvement is progressive with successive sessions.